EP2203385A1 - Method of preparing a controlled porosity geopolymer, the resulting geopolymer and the various applications thereof - Google Patents
Method of preparing a controlled porosity geopolymer, the resulting geopolymer and the various applications thereofInfo
- Publication number
- EP2203385A1 EP2203385A1 EP08839022A EP08839022A EP2203385A1 EP 2203385 A1 EP2203385 A1 EP 2203385A1 EP 08839022 A EP08839022 A EP 08839022A EP 08839022 A EP08839022 A EP 08839022A EP 2203385 A1 EP2203385 A1 EP 2203385A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- geopolymer
- silicate
- porosity
- silica
- compensation
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Ceased
Links
- 229920000876 geopolymer Polymers 0.000 title claims abstract description 102
- 238000000034 method Methods 0.000 title claims abstract description 32
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 82
- 238000009826 distribution Methods 0.000 claims abstract description 59
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 claims abstract description 43
- 229910000323 aluminium silicate Inorganic materials 0.000 claims abstract description 42
- 150000001768 cations Chemical class 0.000 claims abstract description 42
- 239000000377 silicon dioxide Substances 0.000 claims abstract description 37
- HNPSIPDUKPIQMN-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Al]O[Al]=O HNPSIPDUKPIQMN-UHFFFAOYSA-N 0.000 claims abstract description 33
- 239000002245 particle Substances 0.000 claims abstract description 32
- 230000004913 activation Effects 0.000 claims abstract description 31
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 30
- 238000006068 polycondensation reaction Methods 0.000 claims abstract description 10
- 238000004090 dissolution Methods 0.000 claims abstract description 7
- 239000011148 porous material Substances 0.000 claims description 49
- 239000000243 solution Substances 0.000 claims description 49
- 239000000203 mixture Substances 0.000 claims description 42
- 238000002360 preparation method Methods 0.000 claims description 19
- 230000008569 process Effects 0.000 claims description 13
- 150000004760 silicates Chemical class 0.000 claims description 12
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 claims description 11
- 229910052753 mercury Inorganic materials 0.000 claims description 11
- 239000011734 sodium Substances 0.000 claims description 11
- 229910004298 SiO 2 Inorganic materials 0.000 claims description 10
- 239000007787 solid Substances 0.000 claims description 10
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 claims description 9
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 claims description 9
- 229910052700 potassium Inorganic materials 0.000 claims description 9
- 239000011591 potassium Substances 0.000 claims description 9
- 229910052708 sodium Inorganic materials 0.000 claims description 9
- 229910052792 caesium Inorganic materials 0.000 claims description 7
- TVFDJXOCXUVLDH-UHFFFAOYSA-N caesium atom Chemical compound [Cs] TVFDJXOCXUVLDH-UHFFFAOYSA-N 0.000 claims description 7
- 230000003213 activating effect Effects 0.000 claims description 5
- 229910052783 alkali metal Inorganic materials 0.000 claims description 5
- 150000001340 alkali metals Chemical class 0.000 claims description 5
- 229910052784 alkaline earth metal Inorganic materials 0.000 claims description 5
- 150000001342 alkaline earth metals Chemical class 0.000 claims description 5
- 238000006555 catalytic reaction Methods 0.000 claims description 4
- 239000004568 cement Substances 0.000 claims description 4
- 238000001914 filtration Methods 0.000 claims description 4
- 229910001579 aluminosilicate mineral Inorganic materials 0.000 claims description 3
- 239000007864 aqueous solution Substances 0.000 claims description 3
- 239000006227 byproduct Substances 0.000 claims description 3
- 230000003197 catalytic effect Effects 0.000 claims description 3
- 229910001408 cation oxide Inorganic materials 0.000 claims description 3
- 239000013626 chemical specie Substances 0.000 claims description 3
- 239000008119 colloidal silica Substances 0.000 claims description 3
- 238000000926 separation method Methods 0.000 claims description 3
- 239000008262 pumice Substances 0.000 claims description 2
- 239000002585 base Substances 0.000 claims 1
- 239000000463 material Substances 0.000 description 41
- 238000009472 formulation Methods 0.000 description 20
- NLYAJNPCOHFWQQ-UHFFFAOYSA-N kaolin Chemical compound O.O.O=[Al]O[Si](=O)O[Si](=O)O[Al]=O NLYAJNPCOHFWQQ-UHFFFAOYSA-N 0.000 description 10
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 9
- HUCVOHYBFXVBRW-UHFFFAOYSA-M caesium hydroxide Inorganic materials [OH-].[Cs+] HUCVOHYBFXVBRW-UHFFFAOYSA-M 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 5
- 238000002156 mixing Methods 0.000 description 5
- 238000002459 porosimetry Methods 0.000 description 5
- 239000000126 substance Substances 0.000 description 5
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 4
- 230000015572 biosynthetic process Effects 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 4
- 239000003153 chemical reaction reagent Substances 0.000 description 4
- 239000000499 gel Substances 0.000 description 4
- 230000035484 reaction time Effects 0.000 description 4
- 150000004645 aluminates Chemical class 0.000 description 3
- 239000011575 calcium Substances 0.000 description 3
- 239000004567 concrete Substances 0.000 description 3
- 238000010276 construction Methods 0.000 description 3
- 239000010881 fly ash Substances 0.000 description 3
- 238000001033 granulometry Methods 0.000 description 3
- 229910052500 inorganic mineral Inorganic materials 0.000 description 3
- 229920000592 inorganic polymer Polymers 0.000 description 3
- 239000011707 mineral Substances 0.000 description 3
- 238000011160 research Methods 0.000 description 3
- 241000894007 species Species 0.000 description 3
- 238000004876 x-ray fluorescence Methods 0.000 description 3
- OVSKIKFHRZPJSS-UHFFFAOYSA-N 2,4-D Chemical compound OC(=O)COC1=CC=C(Cl)C=C1Cl OVSKIKFHRZPJSS-UHFFFAOYSA-N 0.000 description 2
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 2
- 150000008044 alkali metal hydroxides Chemical class 0.000 description 2
- 239000012670 alkaline solution Substances 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 239000008346 aqueous phase Substances 0.000 description 2
- 239000004566 building material Substances 0.000 description 2
- 229910052791 calcium Inorganic materials 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 229910052900 illite Inorganic materials 0.000 description 2
- 229910052622 kaolinite Inorganic materials 0.000 description 2
- 239000011777 magnesium Substances 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- VGIBGUSAECPPNB-UHFFFAOYSA-L nonaaluminum;magnesium;tripotassium;1,3-dioxido-2,4,5-trioxa-1,3-disilabicyclo[1.1.1]pentane;iron(2+);oxygen(2-);fluoride;hydroxide Chemical compound [OH-].[O-2].[O-2].[O-2].[O-2].[O-2].[F-].[Mg+2].[Al+3].[Al+3].[Al+3].[Al+3].[Al+3].[Al+3].[Al+3].[Al+3].[Al+3].[K+].[K+].[K+].[Fe+2].O1[Si]2([O-])O[Si]1([O-])O2.O1[Si]2([O-])O[Si]1([O-])O2.O1[Si]2([O-])O[Si]1([O-])O2.O1[Si]2([O-])O[Si]1([O-])O2.O1[Si]2([O-])O[Si]1([O-])O2.O1[Si]2([O-])O[Si]1([O-])O2.O1[Si]2([O-])O[Si]1([O-])O2 VGIBGUSAECPPNB-UHFFFAOYSA-L 0.000 description 2
- 229920000642 polymer Polymers 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 229910052678 stilbite Inorganic materials 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 229910021642 ultra pure water Inorganic materials 0.000 description 2
- 239000012498 ultrapure water Substances 0.000 description 2
- 238000005303 weighing Methods 0.000 description 2
- MFGOFGRYDNHJTA-UHFFFAOYSA-N 2-amino-1-(2-fluorophenyl)ethanol Chemical compound NCC(O)C1=CC=CC=C1F MFGOFGRYDNHJTA-UHFFFAOYSA-N 0.000 description 1
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 1
- 229910001018 Cast iron Inorganic materials 0.000 description 1
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 1
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 1
- 229910019142 PO4 Inorganic materials 0.000 description 1
- 241000255972 Pieris <butterfly> Species 0.000 description 1
- 239000004111 Potassium silicate Substances 0.000 description 1
- 229910004283 SiO 4 Inorganic materials 0.000 description 1
- 229910002800 Si–O–Al Inorganic materials 0.000 description 1
- 239000004115 Sodium Silicate Substances 0.000 description 1
- 239000004809 Teflon Substances 0.000 description 1
- 229920006362 Teflon® Polymers 0.000 description 1
- 229920008262 Thermoplastic starch Polymers 0.000 description 1
- 229910010413 TiO 2 Inorganic materials 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 229910001854 alkali hydroxide Inorganic materials 0.000 description 1
- 229910052910 alkali metal silicate Inorganic materials 0.000 description 1
- 229910001583 allophane Inorganic materials 0.000 description 1
- INJRKJPEYSAMPD-UHFFFAOYSA-N aluminum;silicic acid;hydrate Chemical compound O.[Al].[Al].O[Si](O)(O)O INJRKJPEYSAMPD-UHFFFAOYSA-N 0.000 description 1
- 229910001588 amesite Inorganic materials 0.000 description 1
- 229910052849 andalusite Inorganic materials 0.000 description 1
- 229910052788 barium Inorganic materials 0.000 description 1
- DSAJWYNOEDNPEQ-UHFFFAOYSA-N barium atom Chemical compound [Ba] DSAJWYNOEDNPEQ-UHFFFAOYSA-N 0.000 description 1
- 239000000440 bentonite Substances 0.000 description 1
- 229910000278 bentonite Inorganic materials 0.000 description 1
- SVPXDRXYRYOSEX-UHFFFAOYSA-N bentoquatam Chemical compound O.O=[Si]=O.O=[Al]O[Al]=O SVPXDRXYRYOSEX-UHFFFAOYSA-N 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 239000003245 coal Substances 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 230000003750 conditioning effect Effects 0.000 description 1
- 229910052878 cordierite Inorganic materials 0.000 description 1
- 238000007865 diluting Methods 0.000 description 1
- JSKIRARMQDRGJZ-UHFFFAOYSA-N dimagnesium dioxido-bis[(1-oxido-3-oxo-2,4,6,8,9-pentaoxa-1,3-disila-5,7-dialuminabicyclo[3.3.1]nonan-7-yl)oxy]silane Chemical compound [Mg++].[Mg++].[O-][Si]([O-])(O[Al]1O[Al]2O[Si](=O)O[Si]([O-])(O1)O2)O[Al]1O[Al]2O[Si](=O)O[Si]([O-])(O1)O2 JSKIRARMQDRGJZ-UHFFFAOYSA-N 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000010433 feldspar Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 239000008187 granular material Substances 0.000 description 1
- 239000002440 industrial waste Substances 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 1
- 238000004898 kneading Methods 0.000 description 1
- 229910052850 kyanite Inorganic materials 0.000 description 1
- 239000010443 kyanite Substances 0.000 description 1
- 229910052744 lithium Inorganic materials 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 238000005065 mining Methods 0.000 description 1
- 239000000178 monomer Substances 0.000 description 1
- 239000004570 mortar (masonry) Substances 0.000 description 1
- 150000002823 nitrates Chemical class 0.000 description 1
- 125000004430 oxygen atom Chemical group O* 0.000 description 1
- 239000012071 phase Substances 0.000 description 1
- 235000021317 phosphate Nutrition 0.000 description 1
- 150000003013 phosphoric acid derivatives Chemical class 0.000 description 1
- 229910052913 potassium silicate Inorganic materials 0.000 description 1
- 235000019353 potassium silicate Nutrition 0.000 description 1
- NNHHDJVEYQHLHG-UHFFFAOYSA-N potassium silicate Chemical compound [K+].[K+].[O-][Si]([O-])=O NNHHDJVEYQHLHG-UHFFFAOYSA-N 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000009417 prefabrication Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 229910052903 pyrophyllite Inorganic materials 0.000 description 1
- 230000008707 rearrangement Effects 0.000 description 1
- 230000008521 reorganization Effects 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 229910052701 rubidium Inorganic materials 0.000 description 1
- IGLNJRXAVVLDKE-UHFFFAOYSA-N rubidium atom Chemical compound [Rb] IGLNJRXAVVLDKE-UHFFFAOYSA-N 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- LIVNPJMFVYWSIS-UHFFFAOYSA-N silicon monoxide Chemical compound [Si-]#[O+] LIVNPJMFVYWSIS-UHFFFAOYSA-N 0.000 description 1
- 229910052814 silicon oxide Inorganic materials 0.000 description 1
- 239000002893 slag Substances 0.000 description 1
- 229910052911 sodium silicate Inorganic materials 0.000 description 1
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 description 1
- 238000003892 spreading Methods 0.000 description 1
- 230000007480 spreading Effects 0.000 description 1
- 229910052712 strontium Inorganic materials 0.000 description 1
- CIOAGBVUUVVLOB-UHFFFAOYSA-N strontium atom Chemical compound [Sr] CIOAGBVUUVVLOB-UHFFFAOYSA-N 0.000 description 1
- 150000003467 sulfuric acid derivatives Chemical class 0.000 description 1
- 238000001308 synthesis method Methods 0.000 description 1
- 239000010891 toxic waste Substances 0.000 description 1
- 239000010457 zeolite Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/20—Silicates
- C01B33/26—Aluminium-containing silicates, i.e. silico-aluminates
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J21/00—Catalysts comprising the elements, oxides, or hydroxides of magnesium, boron, aluminium, carbon, silicon, titanium, zirconium, or hafnium
- B01J21/16—Clays or other mineral silicates
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/20—Silicates
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
- C04B28/006—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing mineral polymers, e.g. geopolymers of the Davidovits type
- C04B28/008—Mineral polymers other than those of the Davidovits type, e.g. from a reaction mixture containing waterglass
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
- B01J35/63—Pore volume
- B01J35/633—Pore volume less than 0.5 ml/g
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
- B01J35/63—Pore volume
- B01J35/635—0.5-1.0 ml/g
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
- B01J35/64—Pore diameter
- B01J35/647—2-50 nm
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
- B01J35/66—Pore distribution
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P40/00—Technologies relating to the processing of minerals
- Y02P40/10—Production of cement, e.g. improving or optimising the production methods; Cement grinding
Definitions
- the present invention relates to the field of geopolymers and, more particularly, to the field of geopolymers with controlled porosity.
- the present invention aims at providing a method of preparation in which the main formulation parameters make it possible simultaneously to control the total porosity of the geopolymer as well as its porous modes, ie micro-, macro- and mesoporous thus opening the way to an engineering of the porosity of these materials.
- the present invention also relates to the geopolymers obtainable by said process, their various uses and this particularly in the field of catalysis and filtration.
- the initial reactive material contains essentially silica and aluminum from an aluminosilicate source
- the material obtained is amorphous aluminosilicate inorganic polymer [13], [14] termed "geopolymer" [15].
- the geopolymer is prepared by activating the alumino-silicate source from the high pH solution. This preparation consists of kneading together the various components and then keeping the material obtained under defined conditions of temperature, pressure and relative humidity until the final geopolymer is obtained.
- a simplified reaction mechanism is, however, generally accepted [37]: it consists mainly of a dissolution / polycondensation mechanism whose different steps take place simultaneously. Initially, the solid grains of the alumino-silicate source are suspended in the aqueous phase. At high pH, the dissolution of the source aluminosilicates is rapid and leads to the appearance of chemical species (aluminates, silicates, aluminosilicates, etc.) in the activation solution, which phase may also contain silicate species. This process is water consuming.
- the supersaturation of the solution causes the appearance of a gel linked to the polycondensation of the oligomers in the aqueous phase.
- the size of the oligomers formed depends on the size of the compensating cation [38].
- geopolymers develop a high porosity, which makes them particularly advantageous in applications as insulation.
- Geopolymers are also used as binders [16-20] in the formulation of building materials [21, 22], concretes or mortars [23, 24] and fireproof materials [25-27].
- binders [16-20] in the formulation of building materials [21, 22], concretes or mortars [23, 24] and fireproof materials [25-27].
- Several production methods are known [28, 29], allowing their implementation on site or in the context of prefabrications [30, 31].
- geopolymers can be used as a matrix for coating or inerting toxic waste [32-34].
- the porous nature of the geopolymers can make it a particularly interesting support for various applications such as catalysis or filtration.
- the present invention makes it possible to provide a solution to the need presented above and consists of a process making it possible to obtain geopolymers as monolithic materials whose porosity can be controlled as soon as they are formulated.
- the results obtained by the inventors have made it possible to develop a method by which the porosity of the material is as well controlled in the macroporous zone as in the mesoporous zone, said control being applied as much to the total porosity of the material as to 'to the pore distribution of it.
- the term "geopolymer” is intended to mean an amorphous aluminosilicate inorganic polymer. Said polymer is obtained from a reactive material containing essentially silica and aluminum, activated by a strongly alkaline solution, the solid / solution mass ratio in the formulation being low, in particular less than 0.6 and, advantageously, less than 0.5.
- the structure of a geopolymer is composed of an Si-O-Al lattice formed of silicate (SiO 4 ) and aluminate (AlO 4 ) tetrahedra bound at their vertices by oxygen atom sharing. Within this network, there is (are) one (or more) charge compensating cation (s) also called compensation cation (s). These cations symbolized later by the letter M make it possible to compensate for the negative charge of the complex A1O 4 ⁇ .
- the geopolymer prepared according to the process of the present invention can be microporous, macroporous or mesoporous. Advantageously, it is a macroporous or mesoporous geopolymer.
- microporous a material whose pore diameter (dp) is less than 2 nm
- mesoporous a material such as 2 ⁇ dp ⁇ 50 nm
- macroporous a material whose pore diameter is greater than 50 nm.
- the present invention exposes the possibility of defining by the formulation the porosity of the geopolymer and this, more particularly in the macro and mesoporous domains.
- the method which is the subject of the present invention is remarkable because an identical porosity of the final material can come from several different initial formulations.
- To formulate a geopolymer is to choose [5, 10, 36]:
- a high pH activation solution characterized in particular by its amount of water and the amount of soluble silicates it may possibly contain.
- the pore properties of the material are influenced by the specific choices of the species selected for the preparation. Thus, a judicious determination of all the parameters of formulation and implementation allows a priori to control several properties related to the porosity of the geopolymer.
- controlled porosity is used to control the total porosity, the class of the porosity and / or the pore distribution.
- the present invention is therefore characterized by a reasoned choice of certain parameters from the formulation of the geopolymer to be prepared after having first defined the poral characteristics of said geopolymer.
- the present invention therefore relates to a process for preparing a controlled porosity geopolymer comprising a step of dissolution / polycondensation of an aluminosilicate source in an activating solution that may optionally contain silicate components, said process comprising the following successive steps consisting of a. define at least one characteristic of the porosity of the geopolymer to be prepared; b. determining a value or an element for at least one parameter selected from the total amount of water, the total amount of silica, the compensation cation, and the particle size distribution of the possible silicate components, to obtain the characteristic defined in step (a); vs. select said value or said element predetermined in step (b).
- Step (a) of the method according to the present invention consists in defining at least one characteristic selected from the group consisting of the total porosity, the porosity class and the pore distribution such as the pore size distribution in a given class. .
- at least two of these characteristics and, more particularly, the three characteristics are defined in step (a).
- Step (b) of the method according to the present invention can be implemented in different ways.
- this step consists of testing different values (or different elements) for at least one parameter among the previously listed parameters and determining the value (or the element) making it possible to obtain at least one characteristic defined in step (a). ).
- step (b) of the method according to the invention may consist of identifying the value (or the element) making it possible to obtain at least one characteristic defined in step (a) on the basis of previously obtained data. and in particular accessible to the skilled person in scientific publications or patent applications. It may be necessary to repeat the step
- the present invention relates to a process for the preparation of a geopolymer with controlled porosity comprising a step of dissolution / polycondensation of an aluminosilicate source in an activation solution that may optionally contain silicate components, said process comprising a step to select: a pre-determined value for the total quantity of water and / or for the size distribution of the possible silicate components in order to obtain a geopolymer whose porosity accessible to water is between about 15% and 1%; 65%.
- the porosity accessible to water of the geopolymer is of the order of 15%, of the order of 20%, of the order of 25%, of the order of 30%, of the order of 35%.
- % of the order of 40%, of the order of 45%, of the order of 50%, of the order of 55%, of the order of 60% or of the order of 65%; a pre-determined value for the total amount of silica in order to obtain a geopolymer having a monomodal microporosity, mesoporosity or macroporosity and / or
- the work of the inventors has made it possible to show that the total porosity of the geopolymers can be controlled by modifying the formulation parameters of these materials, in particular the water content.
- the amount of water influences the total porosity of the geopolymer presumably by conditioning: the space initially separating the source aluminosilicate solid particles,
- the quantity of water can in particular be fixed via the molar ratio H 2 O / M 2 O with H 2 O corresponding to the sum of the quantity expressed in moles of water present in the activation solution and the quantity expressed in moles of water optionally bound to the alumino-silicate source and M 2 O corresponding to the molar amount of compensation cation oxide in the activation solution.
- H 2 O / M 2 O molar ratio makes it possible to increase the total porosity of the geopolymer thus obtained.
- the inventors have shown that an H 2 O / M 2 O molar ratio greater than 10, advantageously greater than 11 makes it possible to obtain a geopolymer whose porosity accessible to water is greater than 50%.
- the pre-determined value for the particle size distribution of the possible silicate components is advantageously chosen from a pre-determined value of the median diameter of the particle size distribution of the possible silicate components or a predetermined value of the extent of the particle size distribution of the particles. possible silicate components.
- the lower the median diameter of the silicates components used the more the polymer obtained has a porosity accessible to low water.
- the smaller the extent of the particle size distribution of the silicate components the lower the pore distribution of the geopolymer obtained is centered, and therefore the lower the total geopolymer porosity.
- the class of porosity (macropores, mesopores or micropores) can to be chosen as soon as it is implemented by selecting a total concentration of suitable silica.
- the porous mode depends on the porosity proper to the gel. This amounts to modifying the polycondensation behavior, for example by doping the amount of silicate monomers by adding reagents into the activation solution.
- the unreacted silica also seems to lead to a steric hindrance of the residual aqueous poral space, thus to a decrease in the porous mode of the material.
- the particle size distribution of the silica used has an impact on the modalities of space and therefore on the porosity of the material.
- amount of silica is meant the sum of the silica supplied by the aluminosilicate source and the silica possibly present in the activation solution.
- the SiO 2 / M 2 O molar ratio makes it possible to assess the total amount of silica, SiO 2 corresponding to the molar amount of silicon oxide supplied by the alumino-silicate source and the silica possibly present in the activation solution.
- those skilled in the art can obtain and / or calculate these values, without inventive effort, by using standard chemical analyzes, such as weighing or X-ray fluorescence, of all the reagents used.
- a SiO 2 ZM 2 O molar ratio greater than 1 and especially greater than 1.1 makes it possible to obtain a geopolymer exhibiting a monomodal mesoporosity whereas a molar ratio SiO 2 / M 2 O less than 1, in particular less than 0.9, in particular less than 0.8 and, more particularly, less than 0.7 makes it possible to obtain a geopolymer having a monomodal macroporosity.
- the pore distribution and in particular the pore size in a pore range can also be predetermined by an appropriate formulation.
- a geopolymer having a monomodal porosity and, more particularly, a monomodal macroporosity or mesoporosity whose distribution of pore volumes is more or less extensive can be synthesized by choosing one or more suitable compensation cation (s). With the water and silica content fixed in the material, the size and arrangement of the oligomers formed depends on the size of the compensating cations used. The porosity distribution thus controlled seems to be an intrinsic porosity to the initial oligomeric structures.
- the compensation cation is especially chosen from alkali metals, alkaline earth metals and mixtures thereof.
- Mating means mixtures of two or more alkali metals, mixtures of two or more alkaline earth metals and mixtures of one or more alkali metals with one or more alkaline earth metals.
- the alkali metals lithium (Li), sodium (Na), potassium (K), rubidium (Rb) and cesium (Cs) are more particularly preferred.
- the alkaline earth metals magnesium (Mg), calcium (Ca), strontium (Sr) and barium (Ba) are more particularly preferred.
- the amount of compensation cation (s) that can be used in the context of the process of the present invention is between 0.1 and 10, especially between 0.5 and 5, in particular between 0.8 and 2, especially with respect to the molar amount of Al 2 O 3.
- the amount of cation (s) compensation is chosen so that the molar ratio M 2 (VAl 2 O 3 is equal to 1.
- the selection step consists of selecting a compensation cation from potassium, sodium and cesium to obtain an extent of the pore distribution of the geopolymer containing as potassium compensation cation, less than the extent of the pore distribution of the geopolymer containing sodium compensation cation, itself less than the extent of the pore distribution of the geopolymer containing as cesium compensation cation.
- the person skilled in the art will be able to determine, as a function of the compensation cation or of the mixture of compensation cations used, the influence on the porosity distribution without doing proof of a particular inventive effort.
- any alumino-silicate source known to those skilled in the art can be implemented in the context of the process of the invention.
- this Alumino-silicate source is a solid source containing amorphous aluminosilicates.
- amorphous aluminosilicates are chosen in particular from the minerals of natural aluminosilicates such as illite, stilbite, kaolinite, pyrophyllite, andalusite, bentonite, kyanite, milanite, grovenite, amesite, cordierite, feldspar, allophane, etc .; calcined natural aluminosilicate minerals such as metakaolin; synthetic glasses based on pure aluminosilicates; aluminous cement; pumice; calcined by-products or industrial mining residues such as fly ash and blast furnace slags respectively obtained from the burning of coal and during the processing of cast iron ore in a blast furnace; and mixtures thereof.
- natural aluminosilicates such as illite, stilbite, kaolinite, pyrophyllite, andalusite, bentonite, kyanite, milanite, grovenite, amesite, cordierite
- the alumino-silicate source used in the context of the present invention is in a solid form and, advantageously, in the form of a powder or a mixture of particles. These particles have in particular a median diameter (d50) of between 0.1 and 40 ⁇ m, in particular between 0.5 and 20 ⁇ m and, in particular, between 1 and 10 ⁇ m.
- d50 median diameter
- metakaolin is used as alumino-silicate source, it is in the form of particles whose median diameter (d50) determined by laser particle size is about 6 microns.
- particles whose average diameter (d50) is 6 microns means that half of the particles have a diameter of less than 6 microns.
- the skilled person at the time of formulation will, without inventive effort, calculate the amount of alumino-silicate source to be used depending on the composition of the alumino-silicate source used and the desired purpose ie desired properties for the geopolymer. Indeed, depending on the desired properties, a person skilled in the art will be able to choose the most suitable values to achieve this goal and thus will be able to set the molar ratios H 2 O / M 2 O and / or SiO 2 / M 2 O.
- activation solution is intended to mean a strongly alkaline aqueous solution which may optionally contain silicate components.
- strongly alkaline means a solution whose pH is greater than 9, especially greater than 10, in particular greater than 11 and more particularly greater than 12.
- the activation solution comprises the compensation cation or the mixture of compensation cations in the form of an ionic solution or a salt.
- the activation solution is chosen in particular from an aqueous solution of sodium silicate (Na 2 SiO), potassium silicate (K 2 SiO 2), sodium hydroxide (NaOH), potassium hydroxide ( KOH), calcium hydroxide (Ca (OH) 2 ), cesium hydroxide (CsOH) and their sulphates, phosphates and nitrates derivatives, etc ....
- sodium silicate Na 2 SiO
- potassium silicate K 2 SiO 2
- sodium hydroxide NaOH
- potassium hydroxide KOH
- calcium hydroxide Ca (OH) 2
- cesium hydroxide (CsOH) cesium hydroxide
- the silicates components present in the activation solution may be not only the silicates provided by the silicates of the compensation cations present in the activation solution but also other silicates added to the activation solution. These are especially selected from silica, colloidal silica and vitreous silica. It is therefore clear that the silicate components present in the activation solution are either only the silicate (s) provided in the form of silicate (s) of the compensation cations, or only the silicate (s) added (s). ) and selected from silica, colloidal silica and vitreous silica, a mixture of these two sources of silicates.
- the activating solution is prepared by mixing the various elements previously described which compose it. The mixture can be produced with more or less intense stirring depending on the nature of said elements.
- the solid / solution mass ratio is, in the context of the present invention, low, especially less than 0.6 and advantageously less than 0.5. This mass ratio corresponds to the mass of solids (ie alumino-silicate source + compensating cations + silicate components) on the mass of solution (ie activation solution).
- the process for preparing a controlled porosity geopolymer that is the subject of the present invention and, more particularly, the dissolution / polycondensation stages consists, first of all, in mixing the aluminosilicate source with the activation solution while stirring. more or less intense depending on the nature of the alumino-silicate source and the elements contained in the activation solution and then to preserve the material obtained under defined conditions of temperature, pressure and relative humidity until the final geopolymer.
- reaction time is also a function of the compensation cation (s) used.
- the reaction time may be between 5 minutes and 48 hours, in particular between 1 and 42 hours, advantageously between 5 and 36 hours and, in particular, between 10 hours and 24 hours.
- the reaction is carried out under tight conditions and under a pressure corresponding to atmospheric pressure.
- the present invention also relates to a geopolymer capable of being prepared by the method of the invention and having a monomodal mesoporosity with 50% of the pores having an accessibility diameter determined by mercury porosity extending over less than 5 nm (pore distribution strongly refined), between 5 and 10 nm (wider pore distribution) or over 10 nm (spreading pore distribution).
- the present invention also relates to a geopolymer capable of being prepared by the method of the invention and having a monomodal macroporosity with 50% of the pores having an accessibility diameter determined by mercury porosity extending over less than 10 nm (pore distribution strongly refined), between 10 and 50 nm (wider pore distribution) or over 50 nm (spread pore distribution).
- the present invention also relates to a catalytic support and / or species separation chemical composition comprising a geopolymer as defined above and the use of said geopolymer. All known uses of those skilled in the art implementing a geopolymer and in particular the uses described in the prior art cited above are contemplated within the scope of the present invention.
- the present invention relates, more particularly, to the use of a geopolymer as defined previously in catalysis or in filtration.
- Figure 1 shows the pore distribution as a function of mercury porosimetric accessibility diameter for geopolymers of controlled porous modes.
- Figure 2 shows the distribution of pore volumes as a function of mercury porosimetric accessibility diameter for geopolymers of different pore selectivity.
- Figure 3 shows the influence of silica and, more particularly, its particle size distribution on the mercury porosimetric accessibility diameter distribution for geopolymers of controlled porous modes.
- the aluminosilicate source used is metakaolin because this alumino-silicate source makes it possible to obtain more "pure" geopolymers whose properties are globally more homogeneous [39, 40].
- the metakaolin used is Pieri Premix MK (Grace Construction Products), whose composition determined by X-ray fluorescence is reported in Table 1.
- the specific surface area of this material, measured by the Brunauer-Emmet-Teller method, is equal to 19, 9 m 2 / g and the median diameter of the particles (d50), determined by laser granulometry, is equal to 5.9 ⁇ m.
- Table 1 Chemical composition of the meta-kao used.
- alkali metal hydroxide solutions employed were prepared by dissolving in ultrapure water granules of NaOH, KOH ( Prolabo, Rectapur, 98%) and CsOH (Alfa Aesar, 99.9%).
- the silica optionally added to the system is an amorphous silica (BDH) whose average diameter is equal to 128.81 ⁇ m.
- activation solutions containing alkali silicates were prepared.
- the alkali hydroxide solutions were obtained by dissolving the appropriate products in ultrapure water.
- the amorphous silica possibly added to the system is then introduced into these solutions and mixed for 30 minutes.
- the composition of these activation solutions is thus fully described by: the natures of the alkalis used in the formulation and their optional molar ratio, the molar ratio H 2 O / M 2 O, denoted by e, the molar ratio SiO 2 / M 2 O noted s.
- the geopolymer is prepared by mixing metakaolin and the activation solution in a standard laboratory mixer (European Standard EN 196-1) for 1 minute at slow speed and 2 minutes at fast speed. The material is then placed in teflon molds of dimensions 4 * 4 * 16 cm, vibrated for a few seconds, then placed in sealed conditions at 20 0 C and at atmospheric pressure for 24 hours. After this period, the geopolymer is demolded and placed in a sealed bag and stored at ambient pressure and temperature until use.
- a standard laboratory mixer European Standard EN 196-1
- the porosity of the geopolymers was characterized by: - porosimetry accessible to water according to the recommendations of the French Association for Construction (PSAC) and the French Association of Research and Testing on Materials and Constructions (AFREM), this method of measuring porosity is one of the most representative of the total porosity of building materials [43], the porosimetry with mercury intrusion. These measurements were carried out on a Micromeritics Autopore IV 9510 apparatus, whose investigative pressures ranged from 0.2 to 61000 psi.
- Table 2 summarizes measurements of water porosity carried out on geopolymers of different composition. A small variation in the water content strongly impacts the total measured porosity.
- Table 2 Composition of geopolymers and porosity accessible to associated water.
- the objective here is to formulate two materials having controlled and distinct porous modes: the first material must have a monomodal macroporosity centered on 100 nm, the second geopolymer a monomodal mesoporosity centered on 10 nm.
- the objective here is to formulate three materials presenting monomodal mesoporosities whose distribution of pore volumes is more or less extensive.
- the geopolymers were manufactured according to the following formulations:
- 50% of the pores have an access diameter of between 4.1 and 8.8 nm; the sodium geopolymer, the porosity is always monomodal, selective, but more spread distribution because pore range of greater size: 50% of the pores have an access diameter of between 9.9 and 16.5 nm.
- the objective here is to study the influence of the silicates components that may contain the activation solution and, more particularly, the influence of the nature of the silica introduced into the activation solution.
- Tixosil 38 (Precipitated silica from
- Table 3 compares the values of the total porosities of the geopolymers synthesized with Tixosil silicas 331 and 38 to the porosity of a geopolymer synthesized by a BDH precipitated silica.
- the median diameter and the extent of the particle size distribution have a significant influence on the porosity accessible to water: the lower the median diameter, the lower the total porosity.
- Table 4 summarizes the formulations of the geopolymers studied.
- the silica Tixosil 38 makes it possible to obtain geopolymers whose pore dispersion is centered around values smaller than the Tixosil 331.
- the silica Tixosil 38 has a grain size slightly smaller than the Tixosil 331, but especially much less dispersed. It should be emphasized that the porosity obtained is always mesoporous (silica content), refined (potassium compensating cation): the grain size of the silica therefore essentially influences the water-accessible porosity of the material and the characteristic dimensions of the diameter on which the porous mode is centered.
- a judicious formulation of the geopolymers makes it possible to control the macroporosity and / or the mesoporosity of these materials and opens the way to an engineering of the porosity of these materials, amorphous aluminosilicate inorganic polymers.
- Geopolymer stone for construction and decoration included rock residues and a poly (sialate), poly (sialate-siloxo) and / or poly (sialate-disoloxo) geopolymer binder., FR2831905, Editor. 2003. 25. Yan, S., Geopolymer Dry Powder Regenerated Polystyrene Heat Preservation and Heat Insulating Mortar., CN1762884, Editor. 2006.
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Abstract
The present invention relates to a method of preparing a controlled porosity geopolymer, with a step of dissolution/polycondensation of an aluminosilicate source in an activation solution, comprising the following successive steps: (a) defining a feature of the porosity of the geopolymer to be prepared; (b) determining a value or an element for a parameter chosen from the total amount of water, the total amount of silica, the compensating cation, and the particle size distribution of the optional silicate components, making it possible to obtain the feature defined in step (a); and (c) selecting said value or said element pre-determined in step (b). The present invention relates to a geopolymer capable of being prepared by said method and also to the various uses of said geopolymer.
Description
PROCEDE DE PREPARATION D'UN GEOPOLYMERE A POROSITE PROCESS FOR THE PREPARATION OF A POROSITY GEOPOLYMER
CONTRÔLÉE, LE GÉOPOLYMÈRE AINSI OBTENU ET SESCONTROLLED, THE GEOPOLYMER SO OBTAINED AND HIS
DIFFERENTES APPLICATIONSDIFFERENT APPLICATIONS
DESCRIPTIONDESCRIPTION
DOMAINE TECHNIQUETECHNICAL AREA
La présente invention concerne le domaine des géopolymères et, plus particulièrement, le domaine des géopolymères à porosité contrôlée.The present invention relates to the field of geopolymers and, more particularly, to the field of geopolymers with controlled porosity.
La présente invention vise à fournir un procédé de préparation dans lequel les principaux paramètres de formulation permettent de contrôler simultanément la porosité totale du géopolymère ainsi que ses modes poreux, i.e. micro-, macro- et mésoporeux ouvrant ainsi la voie à une ingénierie de la porosité de ces matériaux.The present invention aims at providing a method of preparation in which the main formulation parameters make it possible simultaneously to control the total porosity of the geopolymer as well as its porous modes, ie micro-, macro- and mesoporous thus opening the way to an engineering of the porosity of these materials.
La présente invention concerne également les géopolymères susceptibles d'être obtenus par ledit procédé, leurs différentes utilisations et ce notamment dans le secteur de la catalyse et de la filtration.The present invention also relates to the geopolymers obtainable by said process, their various uses and this particularly in the field of catalysis and filtration.
ETAT DE LA TECHNIQUE ANTERIEURE Depuis une trentaine d'années, l'on sait que la mise en contact de matériaux alumino-silicatés et d'une solution de fort pH peut conduire, sous des conditions expérimentales choisies, à l'obtention de zéolites de synthèse [1] . La nature cristalline et le degré de cristallinité de ces dernières dépendent notamment de la nature des matériaux initiaux utilisés et du rapport massique solution/solide mis en œuvre.
Les sources alumino-silicatées pouvant être utilisées pour cette synthèse sont très variées, qu'il s'agisse de minéraux naturels (illite, stilbite, kaolinite par exemple [2, 3]), de minéraux calcinés (métakaolin [4-6],...) ou de matériaux de substitution, principalement des sous-produits calcinés ou résidus d'exploitation industrielle (cendres volantes [7-12]) . Lorsque le matériau réactif initial contient essentiellement de la silice et de l'aluminium provenant d'une source alumino-silicatée, qu'il est activé par des solutions fortement alcalines et que le rapport massique solide/solution est faible, le matériau obtenu est un polymère inorganique alumino- silicaté amorphe [13], [14] dénommé « géopolymère » [15] .STATE OF THE PRIOR ART For thirty years, it has been known that contacting aluminosilicate materials and a solution of high pH can lead, under selected experimental conditions, to obtaining zeolites of synthesis [1]. The crystalline nature and the degree of crystallinity of the latter depend in particular on the nature of the initial materials used and the solution / solid mass ratio used. The alumino-silicate sources that can be used for this synthesis are very varied, whether they are natural minerals (illite, stilbite, kaolinite for example [2, 3]), calcined minerals (metakaolin [4-6], ...) or substitute materials, mainly calcined by-products or industrial waste (fly ash [7-12]). When the initial reactive material contains essentially silica and aluminum from an aluminosilicate source, is activated by strongly alkaline solutions and the solids / solution mass ratio is low, the material obtained is amorphous aluminosilicate inorganic polymer [13], [14] termed "geopolymer" [15].
Le géopolymère est préparé par activation de la source alumino-silicatée à partir de la solution de fort pH. Cette préparation consiste à malaxer ensemble les différents composants puis à conserver le matériau obtenu dans des conditions définies de température, de pression et d'humidité relative jusqu'à obtention du géopolymère final.The geopolymer is prepared by activating the alumino-silicate source from the high pH solution. This preparation consists of kneading together the various components and then keeping the material obtained under defined conditions of temperature, pressure and relative humidity until the final geopolymer is obtained.
Les réactions précises conduisant à la formation d'un géopolymère également appelées géopolymérisation sont complexes et encore mal comprises. Un mécanisme réactionnel simplifié est cependant généralement accepté [37] : il consiste principalement en un mécanisme de dissolution/polycondensation dont les différentes étapes se déroulent simultanément.
Initialement, les grains solides de la source alumino-silicatée sont en suspension dans la phase aqueuse. A fort pH, la dissolution des alumino- silicates sources est rapide et entraîne l'apparition d'espèces chimiques (aluminates, silicates, alumino- silicates..) dans la solution d' activation, phase pouvant par ailleurs contenir des espèces silicatées. Ce processus est consommateur d'eau.The precise reactions leading to the formation of a geopolymer also called geopolymerization are complex and still poorly understood. A simplified reaction mechanism is, however, generally accepted [37]: it consists mainly of a dissolution / polycondensation mechanism whose different steps take place simultaneously. Initially, the solid grains of the alumino-silicate source are suspended in the aqueous phase. At high pH, the dissolution of the source aluminosilicates is rapid and leads to the appearance of chemical species (aluminates, silicates, aluminosilicates, etc.) in the activation solution, which phase may also contain silicate species. This process is water consuming.
La sursaturation de la solution entraîne l'apparition d'un gel lié à la polycondensation des oligomères dans la phase aqueuse. La taille des oligomères formés dépend de la taille du cation compensateur [38] .The supersaturation of the solution causes the appearance of a gel linked to the polycondensation of the oligomers in the aqueous phase. The size of the oligomers formed depends on the size of the compensating cation [38].
Alors que la polycondensation se poursuit, il se déroule des réorganisations et réarrangements internes conduisant à la formation d'un réseau tridimensionnel alumino-silicaté .As the polycondensation continues, internal reorganizations and rearrangements take place leading to the formation of a three-dimensional alumino-silicate network.
Il est déjà connu que les géopolymères développent une porosité importante, ce qui en fait notamment leur avantage dans les applications comme isolant. Les géopolymères sont également utilisés comme liants [16-20] dans la formulation de matériaux de construction [21, 22], de bétons ou de mortiers [23, 24] et de matériaux résistants au feu [25-27] . Plusieurs modes de production sont connus [28, 29], permettant leur mise en œuvre sur chantier ou dans le cadre de préfabrications [30, 31] . D'autre part, tout comme les ciments Portland silico-calciques usuels, les géopolymères peuvent être employés comme matrice d'enrobage ou d' inertage des déchets toxiques [32-34] .
Comme expliqué ci-dessus le caractère poreux des géopolymères peut en faire un support particulièrement intéressant pour différentes applications comme par exemple en catalyse ou en filtration. Ainsi, il existe un réel besoin d'un procédé de préparation de géopolymères dans le but de disposer, de façon reproductible et maîtrisée, d'un matériau à porosité contrôlée i.e. d'un matériau dont la porosité peut être déterminée et pré-sélectionnée dès la préparation de la formulation dudit matériau.It is already known that geopolymers develop a high porosity, which makes them particularly advantageous in applications as insulation. Geopolymers are also used as binders [16-20] in the formulation of building materials [21, 22], concretes or mortars [23, 24] and fireproof materials [25-27]. Several production methods are known [28, 29], allowing their implementation on site or in the context of prefabrications [30, 31]. On the other hand, as with conventional Portland-calcium cement cements, geopolymers can be used as a matrix for coating or inerting toxic waste [32-34]. As explained above, the porous nature of the geopolymers can make it a particularly interesting support for various applications such as catalysis or filtration. Thus, there is a real need for a process for preparing geopolymers for the purpose of having, in a reproducible and controlled manner, a material with controlled porosity ie of a material whose porosity can be determined and pre-selected as soon as possible. preparing the formulation of said material.
EXPOSÉ DE L'INVENTIONSTATEMENT OF THE INVENTION
La présente invention permet d' apporter une solution au besoin présenté ci-dessus et consiste en un procédé permettant d'obtenir des géopolymères en tant que matériaux monolithiques dont la porosité peut être contrôlée dès leur formulation.The present invention makes it possible to provide a solution to the need presented above and consists of a process making it possible to obtain geopolymers as monolithic materials whose porosity can be controlled as soon as they are formulated.
En effet, les résultats obtenus par les inventeurs ont permis de mettre au point un procédé grâce auquel la porosité du matériau est aussi bien contrôlée dans la zone macroporeuse que dans la zone mésoporeuse, ledit contrôle s' appliquant autant à la porosité totale du matériau qu'à la distribution porale de celui-ci. Par « géopolymère », on entend dans le cadre de la présente invention un polymère inorganique alumino-silicaté amorphe. Ledit polymère est obtenu à partir d'un matériau réactif contenant essentiellement de la silice et de l'aluminium, activé par une solution fortement alcaline, le rapport massique solide/solution dans la formulation étant faible, notamment inférieur à
0,6 et, avantageusement, inférieur à 0,5. La structure d'un géopolymère est composée d'un réseau Si-O-Al formé de tétraèdres de silicates (SiO4) et d'aluminates (AlO4) liés en leurs sommets par partage d'atomes d'oxygène. Au sein de ce réseau, se trouve (nt) un (ou plusieurs) cation (s) compensateur (s) de charge également appelé (s) cation (s) de compensation. Ces cations symbolisés par la suite par la lettre M permettent de compenser la charge négative du complexe A1O4 ~. Le géopolymère préparé selon le procédé de la présente invention peut être microporeux, macroporeux ou mésoporeux. Avantageusement, il s'agit d'un géopolymère macroporeux ou mésoporeux.In fact, the results obtained by the inventors have made it possible to develop a method by which the porosity of the material is as well controlled in the macroporous zone as in the mesoporous zone, said control being applied as much to the total porosity of the material as to 'to the pore distribution of it. In the context of the present invention, the term "geopolymer" is intended to mean an amorphous aluminosilicate inorganic polymer. Said polymer is obtained from a reactive material containing essentially silica and aluminum, activated by a strongly alkaline solution, the solid / solution mass ratio in the formulation being low, in particular less than 0.6 and, advantageously, less than 0.5. The structure of a geopolymer is composed of an Si-O-Al lattice formed of silicate (SiO 4 ) and aluminate (AlO 4 ) tetrahedra bound at their vertices by oxygen atom sharing. Within this network, there is (are) one (or more) charge compensating cation (s) also called compensation cation (s). These cations symbolized later by the letter M make it possible to compensate for the negative charge of the complex A1O 4 ~ . The geopolymer prepared according to the process of the present invention can be microporous, macroporous or mesoporous. Advantageously, it is a macroporous or mesoporous geopolymer.
Rappelons que, d'après l'Union Internationale de Chimie Pure et Appliquée (IUPAC) [35], est qualifié de microporeux, un matériau dont le diamètre des pores (dp) est inférieur à 2 nm, de mésoporeux, un matériau tel que 2 < dp < 50 nm et de macroporeux, un matériau dont le diamètre des pores est supérieur à 50 nm.Recall that, according to the International Union of Pure and Applied Chemistry (IUPAC) [35], is described as microporous, a material whose pore diameter (dp) is less than 2 nm, mesoporous, a material such as 2 <dp <50 nm and macroporous, a material whose pore diameter is greater than 50 nm.
La présente invention expose la possibilité de définir par la formulation la porosité du géopolymère et ce, plus particulièrement dans les domaines macro et mésoporeux. De plus, le procédé objet de la présente invention est remarquable car une porosité identique du matériau final peut provenir de plusieurs formulations initiales différentes.
Formuler un géopolymère revient à choisir [5, 10, 36] :The present invention exposes the possibility of defining by the formulation the porosity of the geopolymer and this, more particularly in the macro and mesoporous domains. In addition, the method which is the subject of the present invention is remarkable because an identical porosity of the final material can come from several different initial formulations. To formulate a geopolymer is to choose [5, 10, 36]:
(1) une source alumino-silicatée,(1) an aluminosilicate source,
(2) un ou plusieurs cation (s) de compensation,(2) one or more compensation cation (s),
(3) une solution d' activation de fort pH, caractérisée en particulier par sa quantité d'eau et la quantité de silicates solubles qu'elle peut éventuellement contenir.(3) a high pH activation solution, characterized in particular by its amount of water and the amount of soluble silicates it may possibly contain.
Les propriétés porales du matériau sont influencées par les choix spécifiques des espèces sélectionnées pour la préparation. Ainsi, une détermination judicieuse de l'ensemble des paramètres de formulation et de mise en œuvre permet de contrôler a priori plusieurs propriétés liées à la porosité du géopolymère .The pore properties of the material are influenced by the specific choices of the species selected for the preparation. Thus, a judicious determination of all the parameters of formulation and implementation allows a priori to control several properties related to the porosity of the geopolymer.
Ainsi, les travaux des inventeurs ont permis de montrer que trois propriétés fondamentales des matériaux poreux peuvent ainsi être prédéfinies par un choix approprié lors de leur préparation : (a' ) la porosité totale ;Thus, the work of the inventors has made it possible to show that three basic properties of the porous materials can thus be predefined by an appropriate choice during their preparation: (a ') total porosity;
(b' ) la classe de porosité (macroporosité, mésoporosité ou microporosité) ; (c' ) la distribution porale et notamment la distribution de la taille des pores dans une classe donnée .(b ') the porosity class (macroporosity, mesoporosity or microporosity); (c ') the pore distribution and in particular the pore size distribution in a given class.
Ainsi, dans le cadre de la présente invention, on entend par « porosité contrôlée » le contrôle de la porosité totale, de la classe de la porosité et/ou de la distribution porale.
La présente invention se caractérise donc par un choix motivé de certains paramètres dès la formulation du géopolymère à préparer après avoir prélablement défini les caractéritiques porales dudit géopolymère.Thus, in the context of the present invention, the term "controlled porosity" is used to control the total porosity, the class of the porosity and / or the pore distribution. The present invention is therefore characterized by a reasoned choice of certain parameters from the formulation of the geopolymer to be prepared after having first defined the poral characteristics of said geopolymer.
La présente invention concerne donc un procédé de préparation d'un géopolymère à porosité contrôlée comprenant une étape de dissolution/polycondensation d'une source alumino- silicatée dans une solution d' activation pouvant éventuellement contenir des composants silicates, ledit procédé comprenant les étapes successives suivantes consistant à a. définir au moins une caractéristique de la porosité du géopolymère à préparer ; b. déterminer une valeur ou un élément pour au moins un paramètre choisi parmi la quantité totale d'eau, la quantité totale de silice, le cation de compensation, et la distribution granulométrique des éventuels composants silicates, permettant d'obtenir la caractéristique définie à l'étape (a) ; c. sélectionner ladite valeur ou ledit élément pré-déterminé (e) à l'étape (b) .The present invention therefore relates to a process for preparing a controlled porosity geopolymer comprising a step of dissolution / polycondensation of an aluminosilicate source in an activating solution that may optionally contain silicate components, said process comprising the following successive steps consisting of a. define at least one characteristic of the porosity of the geopolymer to be prepared; b. determining a value or an element for at least one parameter selected from the total amount of water, the total amount of silica, the compensation cation, and the particle size distribution of the possible silicate components, to obtain the characteristic defined in step (a); vs. select said value or said element predetermined in step (b).
L'étape (a) du procédé selon la présente invention consiste à définir au moins une caractéristique choisie dans le groupe constitué par la porosité totale, la classe de porosité et la distribution porale telle que la distribution de la taille des pores dans une classe donnée.
Avantageusement, au moins deux de ces caractéristiques et, plus particulièrement, les trois caractéristiques sont définies à l'étape (a) .Step (a) of the method according to the present invention consists in defining at least one characteristic selected from the group consisting of the total porosity, the porosity class and the pore distribution such as the pore size distribution in a given class. . Advantageously, at least two of these characteristics and, more particularly, the three characteristics are defined in step (a).
L'étape (b) du procédé selon la présente invention peut être mise en œuvre de différentes façons .Step (b) of the method according to the present invention can be implemented in different ways.
Avantageusement, cette étape consiste à tester différentes valeurs (ou différents éléments) pour au moins un paramètre parmi les paramètres précédemment listés et à déterminer la valeur (ou l'élément) permettant d'obtenir au moins une caractéristique définie à l'étape (a) .Advantageously, this step consists of testing different values (or different elements) for at least one parameter among the previously listed parameters and determining the value (or the element) making it possible to obtain at least one characteristic defined in step (a). ).
En variante, l'étape (b) du procédé selon l'invention peut consister à identifier la valeur (ou l'élément) permettant d'obtenir au moins une caractéristique définie à l'étape (a) sur la base de données préalablement obtenues et notamment accessibles à l'homme du métier dans les publications scientifiques ou les demandes de brevet. II peut être nécessaire de répéter l'étapeAs a variant, step (b) of the method according to the invention may consist of identifying the value (or the element) making it possible to obtain at least one characteristic defined in step (a) on the basis of previously obtained data. and in particular accessible to the skilled person in scientific publications or patent applications. It may be necessary to repeat the step
(b) plusieurs fois et notamment pour chaque caractéristique porale définie.(b) several times and in particular for each defined pore characteristic.
Plus particulièrement, la présente invention concerne un procédé de préparation d'un géopolymère à porosité contrôlée comprenant une étape de dissolution/polycondensation d'une source alumino- silicatée dans une solution d' activation pouvant éventuellement contenir des composants silicates, ledit procédé comprenant une étape consistant à sélectionner :
une valeur pré-déterminée pour la quantité totale d'eau et/ou pour la distribution granulométrique des éventuels composants silicates afin d'obtenir un géopolymère dont la porosité accessible à l'eau est comprise entre de l'ordre de 15 % et de l'ordre de 65 %. Avantageusement, la porosité accessible à l'eau du géopolymère est de l'ordre de 15 %, de l'ordre de 20 %, de l'ordre de 25 %, de l'ordre de 30 %, de l'ordre de 35 %, de l'ordre de 40 %, de l'ordre de 45 %, de l'ordre de 50 %, de l'ordre de 55 %, de l'ordre de 60 % ou de l'ordre de 65 % ; une valeur pré-déterminée pour la quantité totale de silice afin d'obtenir un géopolymère présentant une microporosité, mésoporosité ou macroporosité monomodale et/ouMore particularly, the present invention relates to a process for the preparation of a geopolymer with controlled porosity comprising a step of dissolution / polycondensation of an aluminosilicate source in an activation solution that may optionally contain silicate components, said process comprising a step to select: a pre-determined value for the total quantity of water and / or for the size distribution of the possible silicate components in order to obtain a geopolymer whose porosity accessible to water is between about 15% and 1%; 65%. Advantageously, the porosity accessible to water of the geopolymer is of the order of 15%, of the order of 20%, of the order of 25%, of the order of 30%, of the order of 35%. %, of the order of 40%, of the order of 45%, of the order of 50%, of the order of 55%, of the order of 60% or of the order of 65%; a pre-determined value for the total amount of silica in order to obtain a geopolymer having a monomodal microporosity, mesoporosity or macroporosity and / or
- un élément pré-déterminé correspondant à un cation de compensation particulier afin d'obtenir un géopolymère dont la distribution porale est plus ou moins étendue.a pre-determined element corresponding to a particular compensation cation in order to obtain a geopolymer whose pore distribution is more or less extensive.
Par l'expression « de l'ordre de X% », on entend X% ± 2%.The expression "of the order of X%" means X% ± 2%.
En effet, les travaux des inventeurs ont permis de montrer que la porosité totale des géopolymères peut être contrôlée en modifiant les paramètres de formulation de ces matériaux, en particulier la teneur en eau. Ainsi, sans limitation à une quelconque théorie, la quantité d'eau influence la porosité totale du géopolymère vraisemblablement en conditionnant :
l'espace séparant initialement les particules solides alumino-silicatées sources,In fact, the work of the inventors has made it possible to show that the total porosity of the geopolymers can be controlled by modifying the formulation parameters of these materials, in particular the water content. Thus, without limitation to any theory, the amount of water influences the total porosity of the geopolymer presumably by conditioning: the space initially separating the source aluminosilicate solid particles,
- la porosité interne au gel et liée à la production d'eau lors de la polycondensation, - la concentration en aluminates et silicates en solution, donc la morphologie du gel.the porosity internal to the gel and related to the production of water during the polycondensation, the concentration of aluminates and silicates in solution, and thus the morphology of the gel.
La quantité d'eau peut notamment être fixée via le rapport molaire H2O/M2O avec H2O correspondant à la somme de la quantité exprimée en moles d'eau présente dans la solution d'activation et de la quantité exprimée en moles d'eau éventuellement liée à la source alumino-silicatée et M2O correspondant à la quantité molaire d' oxyde de cations de compensation dans la solution d'activation. L'homme du métier peut obtenir et/ou calculer ces valeurs, sans effort inventif, en utilisant des analyses chimiques standards, telles que pesée ou fluorescence X, de l'ensemble des réactifs mis en œuvre. Ainsi, une augmentation du rapport molaire H2O/M2O permet d'accroître la porosité totale du géopolymère ainsi obtenu. A titre d'exemple et de façon non limitative, les inventeurs ont montré qu'un rapport molaire H2O/M2O supérieur à 10, avantageusement supérieur à 11 permet d'obtenir un géopolymère dont la porosité accessible à l'eau est supérieure à 50 %.The quantity of water can in particular be fixed via the molar ratio H 2 O / M 2 O with H 2 O corresponding to the sum of the quantity expressed in moles of water present in the activation solution and the quantity expressed in moles of water optionally bound to the alumino-silicate source and M 2 O corresponding to the molar amount of compensation cation oxide in the activation solution. Those skilled in the art can obtain and / or calculate these values, without inventive effort, by using standard chemical analyzes, such as weighing or X-ray fluorescence, of all the reagents used. Thus, an increase in the H 2 O / M 2 O molar ratio makes it possible to increase the total porosity of the geopolymer thus obtained. By way of example and without limitation, the inventors have shown that an H 2 O / M 2 O molar ratio greater than 10, advantageously greater than 11 makes it possible to obtain a geopolymer whose porosity accessible to water is greater than 50%.
Les inventeurs ont également mis en évidence que la distribution granulométrique des composants silicates éventuellement présents dans la solution d' activation et notamment le diamètre médian ou l'étendue de cette distribution granulométrique influencent la porosité totale du géopolymère ainsi
obtenu. Ainsi, la valeur pré-déterminée pour la distribution granulométrique des éventuels composants silicates est avantageusement choisie parmi une valeur pré-déterminée du diamètre médian de la distribution granulométrique des éventuels composants silicates ou une valeur pré-déterminée de l'étendue de la distribution granulométrique des éventuels composants silicates. D'une part, plus le diamètre médian des composants silicates mis en œuvre est faible, plus le polymère obtenu présente une porosité accessible à l'eau faible. D'autre part, plus l'étendue de la distribution granulométrique des composants silicates est faible, plus la distribution porale du géopolymère obtenu est centrée sur une valeur faible et, par conséquent, plus la porosité totale du géopolymère est faible .The inventors have also demonstrated that the particle size distribution of the silicate components that may be present in the activation solution and in particular the median diameter or the extent of this particle size distribution influence the total porosity of the geopolymer as well as the got. Thus, the pre-determined value for the particle size distribution of the possible silicate components is advantageously chosen from a pre-determined value of the median diameter of the particle size distribution of the possible silicate components or a predetermined value of the extent of the particle size distribution of the particles. possible silicate components. On the one hand, the lower the median diameter of the silicates components used, the more the polymer obtained has a porosity accessible to low water. On the other hand, the smaller the extent of the particle size distribution of the silicate components, the lower the pore distribution of the geopolymer obtained is centered, and therefore the lower the total geopolymer porosity.
Ainsi, l'homme du métier pourra obtenir un géopolymère dont la porosité totale sera contrôlée en sélectionnant soit une quantité d'eau adéquate, soit des composants silicates présentant une distribution granulométrique adaptée en termes de diamètre médian et/ou en termes d'étendue de distribution granulométrique, soit une quantité d'eau adéquate et des composants silicates présentant une distribution granulométrique adaptée en termes de diamètre médian et/ou en termes d'étendue de distribution granulométrique .Thus, those skilled in the art will be able to obtain a geopolymer whose total porosity will be controlled by selecting either an adequate quantity of water or of silicate components having a particle size distribution adapted in terms of median diameter and / or in terms of particle size distribution, that is to say an adequate amount of water and silicate components having a particle size distribution adapted in terms of median diameter and / or in terms of size distribution range.
De par les travaux des inventeurs, il a également été mis en évidence que la classe de la porosité (macropores, mésopores ou micropores) peut
être choisie dès la mise en œuvre en sélectionnant une concentration totale en silice adaptée.By the work of the inventors, it has also been demonstrated that the class of porosity (macropores, mesopores or micropores) can to be chosen as soon as it is implemented by selecting a total concentration of suitable silica.
Ainsi, à partir d'une quantité d'eau fixée, le mode poreux dépend de la porosité propre au gel. Cela revient à modifier le comportement de polycondensation, par exemple en dopant la quantité de monomères silicates par ajout de réactifs dans la solution d' activation . D'autre part, la silice n'ayant pas réagi semble conduire également à un encombrement stérique de l'espace poral aqueux résiduel, donc à une diminution du mode poreux du matériau. Il est à noter que, comme précédemment expliqué, la distribution granulométrique de la silice utilisée a un impact sur les modalités d'encombrement et donc sur la porosité du matériau.Thus, from a fixed quantity of water, the porous mode depends on the porosity proper to the gel. This amounts to modifying the polycondensation behavior, for example by doping the amount of silicate monomers by adding reagents into the activation solution. On the other hand, the unreacted silica also seems to lead to a steric hindrance of the residual aqueous poral space, thus to a decrease in the porous mode of the material. It should be noted that, as previously explained, the particle size distribution of the silica used has an impact on the modalities of space and therefore on the porosity of the material.
Par « quantité de silice », on entend la somme de la silice apportée par la source alumino- silicatée et de la silice éventuellement présente dans la solution d' activation . Le rapport molaire Siθ2/M2O permet d'apprécier la quantité totale de silice, SiO2 correspondant à la quantité molaire d'oxyde de silicium apporté par la source alumino-silicatée et par la silice éventuellement présente dans la solution d' activation . Comme précisé précédemment, l'homme du métier peut obtenir et/ou calculer ces valeurs, sans effort inventif, en utilisant des analyses chimiques standards, telles que pesée ou fluorescence X, de l'ensemble des réactifs mis en œuvre. Ainsi, un rapport molaire SiO2ZM2O supérieur à 1 et notamment supérieur à 1,1 permet d'obtenir un géopolymère présentant une mésoporosité monomodale alors qu'un rapport molaire
Siθ2/M2O inférieur à 1, notamment inférieur à 0,9, en particulier inférieur à 0,8 et, plus particulièrement, inférieur à 0,7 permet d'obtenir un géopolymère présentant une macroporosité monomodale.By "amount of silica" is meant the sum of the silica supplied by the aluminosilicate source and the silica possibly present in the activation solution. The SiO 2 / M 2 O molar ratio makes it possible to assess the total amount of silica, SiO 2 corresponding to the molar amount of silicon oxide supplied by the alumino-silicate source and the silica possibly present in the activation solution. As previously stated, those skilled in the art can obtain and / or calculate these values, without inventive effort, by using standard chemical analyzes, such as weighing or X-ray fluorescence, of all the reagents used. Thus, a SiO 2 ZM 2 O molar ratio greater than 1 and especially greater than 1.1 makes it possible to obtain a geopolymer exhibiting a monomodal mesoporosity whereas a molar ratio SiO 2 / M 2 O less than 1, in particular less than 0.9, in particular less than 0.8 and, more particularly, less than 0.7 makes it possible to obtain a geopolymer having a monomodal macroporosity.
Enfin, la distribution porale et notamment la taille des pores dans une gamme porale peuvent aussi être prédéterminées par une formulation adéquate. Un géopolymère présentant une porosité monomodale et, tout particulièrement, une macroporosité ou une mésoporosité monomodale dont la distribution des volumes des pores est plus ou moins étendue, peut être synthétisé en choisissant un ou plusieurs cation (s) de compensation adapté (s) . A teneur en eau et en silice fixées dans le matériau, la taille et l'agencement des oligomères formés dépend de la taille des cations compensateurs utilisés. La distribution de la porosité ainsi contrôlée semble donc être une porosité intrinsèque aux structures oligomériques initiales. Le cation de compensation est notamment choisi parmi les métaux alcalins, les métaux alcalino- terreux et leurs mélanges. Par « mélange », on entend des mélanges de deux ou plus métaux alcalins, des mélanges de deux ou plus métaux alcalino-terreux et des mélanges de un ou plus métaux alcalins avec un ou plus métaux alcalino-terreux. Parmi les métaux alcalins, sont plus particulièrement préférés le lithium (Li), le sodium (Na) , le potassium (K) , le rubidium (Rb) et le césium (Cs) . Parmi les métaux alcalino-terreux, sont plus particulièrement préférés le magnésium (Mg) , le calcium (Ca) , le strontium (Sr) et le barium (Ba) .
La quantité de cation (s) de compensation susceptible d'être mise en œuvre dans le cadre du procédé de la présente invention est comprise entre 0,1 et 10, notamment entre 0,5 et 5, en particulier, entre 0,8 et 2, tout particulièrement, par rapport à la quantité molaire de AI2O3. Avantageusement, dans les différentes formulations mises en œuvre dans le cadre de la présente invention, la quantité de cation (s) de compensation est choisie de façon à ce que le rapport molaire M2(VAl2O3 soit égal à 1.Finally, the pore distribution and in particular the pore size in a pore range can also be predetermined by an appropriate formulation. A geopolymer having a monomodal porosity and, more particularly, a monomodal macroporosity or mesoporosity whose distribution of pore volumes is more or less extensive, can be synthesized by choosing one or more suitable compensation cation (s). With the water and silica content fixed in the material, the size and arrangement of the oligomers formed depends on the size of the compensating cations used. The porosity distribution thus controlled seems to be an intrinsic porosity to the initial oligomeric structures. The compensation cation is especially chosen from alkali metals, alkaline earth metals and mixtures thereof. "Mixing" means mixtures of two or more alkali metals, mixtures of two or more alkaline earth metals and mixtures of one or more alkali metals with one or more alkaline earth metals. Among the alkali metals, lithium (Li), sodium (Na), potassium (K), rubidium (Rb) and cesium (Cs) are more particularly preferred. Among the alkaline earth metals, magnesium (Mg), calcium (Ca), strontium (Sr) and barium (Ba) are more particularly preferred. The amount of compensation cation (s) that can be used in the context of the process of the present invention is between 0.1 and 10, especially between 0.5 and 5, in particular between 0.8 and 2, especially with respect to the molar amount of Al 2 O 3. Advantageously, in the various formulations used in the context of the present invention, the amount of cation (s) compensation is chosen so that the molar ratio M 2 (VAl 2 O 3 is equal to 1.
Ainsi, à titre d'exemples et dans le cadre des cations de compensation alcalins, l'étape de sélection consiste à sélectionner un cation de compensation parmi le potassium, le sodium et le césium pour obtenir une étendue de la distribution porale du géopolymère contenant comme cation de compensation du potassium, inférieure à l'étendue de la distribution porale du géopolymère contenant comme cation de compensation du sodium, elle-même inférieure à l'étendue de la distribution porale du géopolymère contenant comme cation de compensation du césium. Sur la base de l'exemple IV dans la partie expérimentale ci-après, l'homme du métier saura déterminer en fonction du cation de compensation ou du mélange de cations de compensation mis en œuvre, l'influence sur la répartition de porosité sans faire preuve d'un effort inventif particulier.Thus, as examples and in the context of the alkaline compensation cations, the selection step consists of selecting a compensation cation from potassium, sodium and cesium to obtain an extent of the pore distribution of the geopolymer containing as potassium compensation cation, less than the extent of the pore distribution of the geopolymer containing sodium compensation cation, itself less than the extent of the pore distribution of the geopolymer containing as cesium compensation cation. On the basis of Example IV in the experimental part below, the person skilled in the art will be able to determine, as a function of the compensation cation or of the mixture of compensation cations used, the influence on the porosity distribution without doing proof of a particular inventive effort.
Toute source alumino-silicatée connue de l'homme du métier peut être mise en œuvre dans le cadre du procédé de l'invention. Avantageusement, cette
source alumino-silicatée est une source solide contenant des alumino-silicates amorphes. Ces alumino- silicates amorphes sont notamment choisis parmi les minéraux d' alumino-silicates naturels tels que illite, stilbite, kaolinite, pyrophyllite, andalousite, bentonite, kyanite, milanite, grovénite, amésite, cordiérite, feldspath, allophane, etc.. ; des minéraux d' alumino-silicates naturels calcinés tels que le métakaolin ; des verres synthétiques à base d' alumino- silicates purs ; ciment alumineux ; de la ponce ; des sous-produits calcinés ou résidus d'exploitation industrielle tels que des cendres volantes et des laitiers de haut fourneau respectivement obtenus à partir de la combustion du charbon et lors de la transformation du minerai de fer en fonte dans un haut fourneau ; et des mélanges de ceux-ci.Any alumino-silicate source known to those skilled in the art can be implemented in the context of the process of the invention. Advantageously, this Alumino-silicate source is a solid source containing amorphous aluminosilicates. These amorphous aluminosilicates are chosen in particular from the minerals of natural aluminosilicates such as illite, stilbite, kaolinite, pyrophyllite, andalusite, bentonite, kyanite, milanite, grovenite, amesite, cordierite, feldspar, allophane, etc .; calcined natural aluminosilicate minerals such as metakaolin; synthetic glasses based on pure aluminosilicates; aluminous cement; pumice; calcined by-products or industrial mining residues such as fly ash and blast furnace slags respectively obtained from the burning of coal and during the processing of cast iron ore in a blast furnace; and mixtures thereof.
La source alumino-silicatée mise en œuvre dans le cadre de la présente invention se trouve sous une forme solide et, avantageusement, sous la forme d'une poudre ou d'un mélange de particules. Ces particules ont notamment un diamètre médian (d50) compris entre 0,1 et 40 μm, en particulier entre 0,5 et 20 μm et, tout particulièrement, entre 1 et 10 μm. A titre d'exemple et de façon non exhaustive, lorsque du métakaolin est utilisé comme source alumino-silicatée, il se trouve sous la forme de particules dont le diamètre médian (d50) déterminé par granulométrie laser est d'environ 6 μm. Pour rappel, des particules dont le diamètre moyen (d50) est de 6 μm signifie que la moitié des particules présentent un diamètre inférieur à 6 μm.
L'homme du métier au moment de la formulation saura, sans effort inventif, calculer la quantité de source alumino-silicatée à utiliser en fonction de la composition de la source alumino- silicatée utilisée et du but recherché i.e. des propriétés souhaitées pour le géopolymère. En effet, en fonction des propriétés recherchées, l'homme du métier saura choisir les valeurs les mieux adaptées pour atteindre ce but et donc saura fixer les rapports molaires H2O/M2O et/ou SiO2/M2O.The alumino-silicate source used in the context of the present invention is in a solid form and, advantageously, in the form of a powder or a mixture of particles. These particles have in particular a median diameter (d50) of between 0.1 and 40 μm, in particular between 0.5 and 20 μm and, in particular, between 1 and 10 μm. By way of example and non-exhaustively, when metakaolin is used as alumino-silicate source, it is in the form of particles whose median diameter (d50) determined by laser particle size is about 6 microns. As a reminder, particles whose average diameter (d50) is 6 microns means that half of the particles have a diameter of less than 6 microns. The skilled person at the time of formulation will, without inventive effort, calculate the amount of alumino-silicate source to be used depending on the composition of the alumino-silicate source used and the desired purpose ie desired properties for the geopolymer. Indeed, depending on the desired properties, a person skilled in the art will be able to choose the most suitable values to achieve this goal and thus will be able to set the molar ratios H 2 O / M 2 O and / or SiO 2 / M 2 O.
Par « solution d' activation », on entend dans le cadre de la présente invention une solution aqueuse fortement alcaline pouvant éventuellement contenir des composants silicates. Par « fortement alcaline », on entend une solution dont le pH est supérieur à 9, notamment supérieur à 10, en particulier, supérieur à 11 et, plus particulièrement supérieur à 12. La solution d' activation comprend le cation de compensation ou le mélange de cations de compensation sous forme d'une solution ionique ou d'un sel. Ainsi, la solution d' activation est notamment choisie parmi une solution aqueuse de silicate de sodium (Na2SiOs) , de silicate de potassium (K2SiO2) , d'hydroxyde de sodium (NaOH), d'hydroxyde de potassium (KOH), d'hydroxyde de calcium (Ca(OH)2), d'hydroxyde de césium (CsOH) et leurs dérivés sulfates, phosphates et nitrates, etc.... L'homme du métier connait différentes façons de préparer une telle solution d' activation soit
en diluant des compositions commerciales existantes, soit en la préparant de façon extemporanée . L'homme du métier connaît également différentes façons pour ajuster le pH jusqu'à la valeur souhaitée, si nécessaire.In the context of the present invention, the term "activation solution" is intended to mean a strongly alkaline aqueous solution which may optionally contain silicate components. By "strongly alkaline" means a solution whose pH is greater than 9, especially greater than 10, in particular greater than 11 and more particularly greater than 12. The activation solution comprises the compensation cation or the mixture of compensation cations in the form of an ionic solution or a salt. Thus, the activation solution is chosen in particular from an aqueous solution of sodium silicate (Na 2 SiO), potassium silicate (K 2 SiO 2), sodium hydroxide (NaOH), potassium hydroxide ( KOH), calcium hydroxide (Ca (OH) 2 ), cesium hydroxide (CsOH) and their sulphates, phosphates and nitrates derivatives, etc .... The skilled person knows different ways of preparing such activation solution either by diluting existing commercial compositions, either by preparing it extemporaneously. Those skilled in the art also know different ways to adjust the pH to the desired value, if necessary.
Les composants silicates présents dans la solution d' activation peuvent être non seulement les silicates apportés par les silicates des cations de compensation présents dans la solution d' activation mais aussi d'autres silicates ajoutés à la solution d' activation . Ces derniers sont notamment choisis parmi la silice, la silice colloïdale et la silice vitreuse. Il est donc clair que les composants silicates présents dans la solution d' activation sont soit uniquement le ou les silicate (s) apporté (s) sous forme de silicates des cations de compensation, soit uniquement le ou les silicate (s) ajouté (s) et choisi (s) parmi la silice, la silice colloïdale et la silice vitreuse, soit un mélange de ces deux sources de silicates. La solution d' activation est préparée en mélangeant les différents éléments précédemment décrits qui la composent. Le mélange peut être réalisé sous une agitation plus ou moins intense en fonction de la nature desdits éléments .The silicates components present in the activation solution may be not only the silicates provided by the silicates of the compensation cations present in the activation solution but also other silicates added to the activation solution. These are especially selected from silica, colloidal silica and vitreous silica. It is therefore clear that the silicate components present in the activation solution are either only the silicate (s) provided in the form of silicate (s) of the compensation cations, or only the silicate (s) added (s). ) and selected from silica, colloidal silica and vitreous silica, a mixture of these two sources of silicates. The activating solution is prepared by mixing the various elements previously described which compose it. The mixture can be produced with more or less intense stirring depending on the nature of said elements.
A titre d'exemple et en utilisant comme source alumino-silicatée le métakaolin dont la composition chimique est donnée dans le Tableau 1 ci- après, le rapport massique solide/solution est, dans le cadre de la présente invention, faible, notamment inférieur à 0,6 et avantageusement inférieur à 0,5. Ce
rapport massique correspond à la masse de solides (i.e. source alumino-silicatée + cations de compensation + composants silicates) sur la masse de solution (i.e. solution d' activation) .By way of example and using as an aluminosilicate source the metakaolin, the chemical composition of which is given in Table 1 below, the solid / solution mass ratio is, in the context of the present invention, low, especially less than 0.6 and advantageously less than 0.5. This mass ratio corresponds to the mass of solids (ie alumino-silicate source + compensating cations + silicate components) on the mass of solution (ie activation solution).
Le procédé de préparation d'un géopolymère à porosité contrôlée objet de la présente invention et, plus particulièrement, les étapes de dissolution/polycondensation consiste, tout d'abord, à mélanger la source alumino-silicatée avec la solution d' activation sous une agitation plus ou moins intense en fonction de la nature de la source alumino-silicatée et des éléments contenus dans la solution d' activation puis à conserver le matériau obtenu dans des conditions définies de température, de pression et d'humidité relative jusqu'à obtention du géopolymère final.The process for preparing a controlled porosity geopolymer that is the subject of the present invention and, more particularly, the dissolution / polycondensation stages consists, first of all, in mixing the aluminosilicate source with the activation solution while stirring. more or less intense depending on the nature of the alumino-silicate source and the elements contained in the activation solution and then to preserve the material obtained under defined conditions of temperature, pressure and relative humidity until the final geopolymer.
Ces différentes étapes sont effectuées à une température comprise entre 20 et 1200C et notamment entre 20 et 1000C. Le temps de réaction jusqu'à l'obtention du géopolymère à porosité contrôlée dépendra de la température choisie dans la gamme de températures ci-dessus. En effet, plus la température est proche de la température ambiante, plus le temps de réaction est long. Il convient de noter que le temps de réaction est également fonction du (ou des) cation (s) de compensation utilisé (s) . A titre d'exemples, le temps de réaction pourra être compris entre 5 minutes et 48 heures, notamment entre 1 et 42 heures, avantageusment entre 5 et 36 heures et, en particulier, entre 10 heures et 24 heures.
L'homme du métier connaît les conditions optimales de pression et d'humidité relative à utiliser, lors de ces étapes, en fonction des différents réactifs mis en œuvre (i.e. source alumino- silicatée et éléments présents dans la solution d' activation) . A titre d'exemple et de façon non limitative, la réaction est effectuée en conditions étanches et sous une pression correspondant à la pression atmosphérique.These different steps are carried out at a temperature of between 20 and 120 ° C. and in particular between 20 and 100 ° C. The reaction time until obtaining the geopolymer with controlled porosity will depend on the temperature chosen in the temperature range. -above. Indeed, the higher the temperature is close to the ambient temperature, the longer the reaction time is. It should be noted that the reaction time is also a function of the compensation cation (s) used. By way of examples, the reaction time may be between 5 minutes and 48 hours, in particular between 1 and 42 hours, advantageously between 5 and 36 hours and, in particular, between 10 hours and 24 hours. Those skilled in the art know the optimum conditions of pressure and relative humidity to be used, during these stages, as a function of the different reagents used (ie aluminosilicate source and elements present in the activation solution). By way of example and without limitation, the reaction is carried out under tight conditions and under a pressure corresponding to atmospheric pressure.
La présente invention concerne également un géopolymère susceptible d'être préparé par le procédé de l'invention et présentant une mésoporosité monomodale avec 50% des pores présentant un diamètre d'accessibilité déterminé par porosité mercure s' étendant sur moins de 5 nm (répartition porale fortement affinée) , entre 5 et 10 nm (répartition porale plus large) ou sur plus de 10 nm (répartition porale étalée) . La présente invention concerne également un géopolymère susceptible d'être préparé par le procédé de l'invention et présentant une macroporosité monomodale avec 50% des pores présentant un diamètre d'accessibilité déterminé par porosité mercure s' étendant sur moins de 10 nm (répartition porale fortement affinée), entre 10 et 50 nm (répartition porale plus large) ou sur plus de 50 nm (répartition porale étalée) .The present invention also relates to a geopolymer capable of being prepared by the method of the invention and having a monomodal mesoporosity with 50% of the pores having an accessibility diameter determined by mercury porosity extending over less than 5 nm (pore distribution strongly refined), between 5 and 10 nm (wider pore distribution) or over 10 nm (spreading pore distribution). The present invention also relates to a geopolymer capable of being prepared by the method of the invention and having a monomodal macroporosity with 50% of the pores having an accessibility diameter determined by mercury porosity extending over less than 10 nm (pore distribution strongly refined), between 10 and 50 nm (wider pore distribution) or over 50 nm (spread pore distribution).
La présente invention concerne également un support catalytique et/ou de séparation d'espèces
chimiques comprenant un géopolymère tel que précédemment défini et l'utilisation dudit géopolymère. Toutes les utilisations connues de l'homme du métier mettant en œuvre un géopolymère et notamment les utilisations décrites dans l'art antérieur précédemment cité sont envisagées dans le cadre de la présente invention. La présente invention concerne, plus particulièrement, l'utilisation d'un géopolymère tel que précédemment défini en catalyse ou en filtration.The present invention also relates to a catalytic support and / or species separation chemical composition comprising a geopolymer as defined above and the use of said geopolymer. All known uses of those skilled in the art implementing a geopolymer and in particular the uses described in the prior art cited above are contemplated within the scope of the present invention. The present invention relates, more particularly, to the use of a geopolymer as defined previously in catalysis or in filtration.
L' invention sera mieux comprise à la lecture des figures et exemples qui suivent. Ceux-ci n'ont pas pour but de limiter l'invention dans ses applications, il ne s'agit que d'illustrer ici les possibilités offertes par ce nouveau développement de la technique.The invention will be better understood on reading the figures and examples which follow. These are not intended to limit the invention in its applications, it is only to illustrate here the possibilities offered by this new development of the technique.
BRÈVE DESCRIPTION DES DESSINSBRIEF DESCRIPTION OF THE DRAWINGS
La Figure 1 présente la distribution des pores en fonction du diamètre d'accessibilité déterminé par porosimétrie mercure pour des géopolymères de modes poreux contrôlés.Figure 1 shows the pore distribution as a function of mercury porosimetric accessibility diameter for geopolymers of controlled porous modes.
La Figure 2 présente la distribution des volumes des pores en fonction du diamètre d'accessibilité déterminé par porosimétrie mercure pour des géopolymères de sélectivité porale différente. La Figure 3 présente l'influence de la silice et, plus particulièrement, de sa distribution granulométrique sur la distribution du diamètre d'accessibilité déterminé par porosimétrie mercure pour des géopolymères de modes poreux contrôlés.
EXPOSE DETAILLE DE MODES DE REALISATION PARTICULIERSFigure 2 shows the distribution of pore volumes as a function of mercury porosimetric accessibility diameter for geopolymers of different pore selectivity. Figure 3 shows the influence of silica and, more particularly, its particle size distribution on the mercury porosimetric accessibility diameter distribution for geopolymers of controlled porous modes. DETAILED DESCRIPTION OF PARTICULAR EMBODIMENTS
I : Matériaux utilisés , choix de formulation et méthodes .I: Materials used, choice of formulation and methods.
1.1. Source alumino-silicatée.1.1. Alumino-silicate source.
Dans l'ensemble des exemples suivants, la source aluminosilicatée utilisée est du métakaolin car cette source alumino-silicatée permet d'obtenir des géopolymères plus « purs » et dont les propriétés sont globalement plus homogènes [39, 40] .In all of the following examples, the aluminosilicate source used is metakaolin because this alumino-silicate source makes it possible to obtain more "pure" geopolymers whose properties are globally more homogeneous [39, 40].
Le métakaolin employé est du Pieri Premix MK (Grâce Construction Products) , dont la composition déterminée par fluorescence X est reportée dans le tableau 1. La surface spécifique de ce matériau, mesurée par la méthode Brunauer-Emmet-Teller, est égale à 19,9 m2 /g et le diamètre médian des particules (d50), déterminé par granulométrie laser, est égal à 5.9μm.The metakaolin used is Pieri Premix MK (Grace Construction Products), whose composition determined by X-ray fluorescence is reported in Table 1. The specific surface area of this material, measured by the Brunauer-Emmet-Teller method, is equal to 19, 9 m 2 / g and the median diameter of the particles (d50), determined by laser granulometry, is equal to 5.9 μm.
Tableau 1 : Composition chimique du métakao l in empl oyé .Table 1: Chemical composition of the meta-kao used.
% mas sique SiO2 Al2O3 CaO3 Fe2O3 TiO2 K2O Na2O MgO P2O5 % masic SiO 2 Al 2 O 3 CaO 3 Fe 2 O 3 TiO 2 K 2 O Na 2 O MgO P 2 O 5
Métakaolin 54 , 40 38 , 4 0 , 10 1 , 27 1 , 60 0 , 62 < 0 , 20 < 0 , 20 /Metakaolin 54, 40, 38, 40, 1, 27 1, 60 0, 62 <0, 20 <0, 20 /
1.2. Cations compensateurs .1.2. Cation compensators.
Dans l'ensemble des exemples suivants, les cations compensateurs retenus sont des alcalins. Ces cas sont en effet les plus fréquemment rencontrés dans la littérature ([40-42] par exemple) ; ils constituent donc une meilleure illustration du propos.In all of the following examples, the compensating cations retained are alkalis. These cases are indeed the most frequently encountered in the literature ([40-42] for example); they are therefore a better illustration of the subject.
D'autre part, afin de maximiser les réactions de géopolymérisation et d'assurer l' électroneutralité du matériau, la quantité d'alcalin
introduite dans le mélange a été fixée de telle sorte que le rapport global M2O/AI2O3 soit égal à 1. Les solutions d'hydroxyde d'alcalins employées ont été préparées par dissolution dans de l'eau ultrapure de granules de NaOH, de KOH (Prolabo, Rectapur, 98%) et de CsOH (Alfa Aesar, 99,9%) .On the other hand, in order to maximize the geopolymerization reactions and ensure the electroneutrality of the material, the amount of alkaline The alkali metal hydroxide solutions employed were prepared by dissolving in ultrapure water granules of NaOH, KOH ( Prolabo, Rectapur, 98%) and CsOH (Alfa Aesar, 99.9%).
1.3. Silice.1.3. Silica.
La silice éventuellement ajoutée au système est une silice amorphe (BDH) dont le diamètre moyen est égal à 128,81 μm.The silica optionally added to the system is an amorphous silica (BDH) whose average diameter is equal to 128.81 μm.
1.4. Méthode de synthèse .1.4. Synthesis method.
Le mélange des constituants s'est déroulé en deux étapes.The mixing of the components took place in two stages.
Au cours de la première étape, les solutions d' activation contenant des silicates alcalins ont été préparées. Les solutions d'hydroxyde d'alcalins ont été obtenues par dissolution des produits appropriés dans de l'eau ultrapure. La silice amorphe éventuellement ajoutée au système est ensuite introduite dans ces solutions et mélangée pendant 30 minutes. La composition de ces solutions d' activation est ainsi entièrement décrite par : les natures des alcalins utilisées dans la formulation et leur éventuel rapport molaire, le rapport molaire H2O/M2O, noté e, le rapport molaire Siθ2/M2O noté s.In the first step, activation solutions containing alkali silicates were prepared. The alkali hydroxide solutions were obtained by dissolving the appropriate products in ultrapure water. The amorphous silica possibly added to the system is then introduced into these solutions and mixed for 30 minutes. The composition of these activation solutions is thus fully described by: the natures of the alkalis used in the formulation and their optional molar ratio, the molar ratio H 2 O / M 2 O, denoted by e, the molar ratio SiO 2 / M 2 O noted s.
Au cours de la seconde étape, le géopolymère est préparé par mélange du métakaolin et de
la solution d' activation dans un malaxeur normalisé de laboratoire (Norme Européenne EN 196-1) durant 1 minute à vitesse lente et 2 minutes à vitesse rapide. Le matériau est ensuite mis en place dans des moules en téflon de dimensions 4*4*16 cm, vibré durant quelques secondes, puis placé en conditions étanches à 200C et à pression atmosphérique pendant 24 heures. Après cette période, le géopolymère est démoulé puis placé en sac étanche et conservé à pression et température ambiantes jusqu'à utilisation.In the second step, the geopolymer is prepared by mixing metakaolin and the activation solution in a standard laboratory mixer (European Standard EN 196-1) for 1 minute at slow speed and 2 minutes at fast speed. The material is then placed in teflon molds of dimensions 4 * 4 * 16 cm, vibrated for a few seconds, then placed in sealed conditions at 20 0 C and at atmospheric pressure for 24 hours. After this period, the geopolymer is demolded and placed in a sealed bag and stored at ambient pressure and temperature until use.
1.5. Méthodes expérimentales .1.5. Experimental methods.
La porosité des géopolymères a été caractérisée par : - la porosimétrie accessible à l'eau selon les recommandations de l'Association Française pour la Construction (AFPC) et de l'Association Française de Recherches et d'Essais sur les Matériaux et les Constructions (AFREM) , cette méthode de mesure de la porosité est l'une des plus représentatives de la porosité totale des matériaux de construction [43], la porosimétrie à intrusion de mercure. Ces mesures ont été effectuées sur un appareillage Micromeritics Autopore IV 9510, dont les pressions d'investigation ont varié de 0,2 à 61000 psi.The porosity of the geopolymers was characterized by: - porosimetry accessible to water according to the recommendations of the French Association for Construction (PSAC) and the French Association of Research and Testing on Materials and Constructions ( AFREM), this method of measuring porosity is one of the most representative of the total porosity of building materials [43], the porosimetry with mercury intrusion. These measurements were carried out on a Micromeritics Autopore IV 9510 apparatus, whose investigative pressures ranged from 0.2 to 61000 psi.
II : Contrôle de la porosité totale par la quantité d'eau.II: Control of the total porosity by the quantity of water.
Il est possible de contrôler la porosité totale des géopolymères en modifiant les paramètres de
formulation de ces matériaux, en particulier la teneur en eau.It is possible to control the total porosity of geopolymers by changing the parameters of formulation of these materials, especially the water content.
Le tableau 2 récapitule des mesures de porosité à l'eau menées sur des géopolymères de composition différente. Une faible variation de la teneur en eau impacte fortement la porosité totale mesurée .Table 2 summarizes measurements of water porosity carried out on geopolymers of different composition. A small variation in the water content strongly impacts the total measured porosity.
Tableau 2 : Composition des géopolymères et porosité accessible à l'eau associée.Table 2: Composition of geopolymers and porosity accessible to associated water.
III : Contrôle du mode poreux par la quantité de silice.III: Control of the porous mode by the amount of silica.
L'objectif est ici de formuler deux matériaux présentant des modes poreux contrôlés et distincts : le premier matériau doit présenter une macroporosité monomodale centrée sur 100 nm, le second géopolymère une mésoporosité monomodale centrée sur 10 nm.The objective here is to formulate two materials having controlled and distinct porous modes: the first material must have a monomodal macroporosity centered on 100 nm, the second geopolymer a monomodal mesoporosity centered on 10 nm.
Les deux géopolymères ont été fabriqués selon les formulations suivantes :Both geopolymers were manufactured according to the following formulations:
Cation compensateur : sodium uniquement, s=l, 2, e=12
Cation compensateur : sodium uniquement, s=0, 6, e=12Counterbalance cation: sodium only, s = 1, 2, e = 12 Compensation cation: sodium only, s = 0, 6, e = 12
Les analyses effectuées sur ces matériaux par porosimétrie mercure (figure 1) montrent clairement que le cahier des charges est rempli et que les diamètres d'accès aux pores correspondent à la contrainte initiale.The analyzes carried out on these materials by mercury porosimetry (FIG. 1) clearly show that the specifications are fulfilled and that the pore access diameters correspond to the initial stress.
IV : Contrôle de la distribution porale par la nature du cation compensanteur .IV: Control of the pore distribution by the nature of the compensating cation.
L'objectif est ici de formuler trois matériaux présentant des mésoporosités monomodales dont la distribution des volumes des pores est plus ou moins étendue . Les géopolymères ont été fabriqués selon les formulations suivantes :The objective here is to formulate three materials presenting monomodal mesoporosities whose distribution of pore volumes is more or less extensive. The geopolymers were manufactured according to the following formulations:
Cation compensateur : sodium uniquement, s=l, 2, e=12Counterbalance cation: sodium only, s = 1, 2, e = 12
Cation compensateur : potassium uniquement, s=l, 2, e=12Counterbalance cation: potassium only, s = 1, 2, e = 12
Cation compensateur : césium uniquement, s=l, 2, e=12Compensation cation: cesium only, s = 1, 2, e = 12
Les analyses effectuées sur ces matériaux par porosimétrie mercure (figure 2) montrent clairement que le cahier des charges est rempli : le géopolymère au potassium présente une porosité monomodale dont la distribution est fortement affinée puisque plus de 50% des pores ont un diamètre d'accès compris entre 4,7 et 6,1 nm ;
le géopolymère au césium présente également un unique mode poreux, mais dont la répartition porale est plus large que celle du géopolymère au potassium :The analyzes carried out on these materials by mercury porosimetry (Figure 2) clearly show that the specifications are fulfilled: the potassium geopolymer has a monomodal porosity whose distribution is highly refined since more than 50% of the pores have a diameter of access between 4.7 and 6.1 nm; the cesium geopolymer also has a unique porous mode, but the pore distribution is wider than that of potassium geopolymer:
50% des pores ont un diamètre d'accès compris entre 4,1 et 8,8 nm ; le géopolymère au sodium, la porosité est toujours monomodale, sélective, mais de distribution plus étalée car de gamme de pores de taille supérieure : 50% des pores ont un diamètre d'accès compris entre 9,9 et 16,5 nm.50% of the pores have an access diameter of between 4.1 and 8.8 nm; the sodium geopolymer, the porosity is always monomodal, selective, but more spread distribution because pore range of greater size: 50% of the pores have an access diameter of between 9.9 and 16.5 nm.
V : Influence de la nature des éventuels composants silicates .V: Influence of the nature of the possible silicates components.
L'objectif ici est d'étudier l'influence des composants silicates que peut contenir la solution d' activation et, plus particulièrement, l'influence de la nature de la silice introduite dans la solution d' activation .The objective here is to study the influence of the silicates components that may contain the activation solution and, more particularly, the influence of the nature of the silica introduced into the activation solution.
Ainsi, trois types de silice différentes ont été introduites dans la solution d' activation :Thus, three different types of silica have been introduced into the activation solution:
Silice précipitée (BDH) dont la granulométrie est dlO = 75,29 μm, d50 = 128,81 μm, d90 = 216, 18 μm ;Precipitated silica (BDH) whose particle size is d10 = 75.29 μm, d50 = 128.81 μm, d90 = 216, 18 μm;
Tixosil 331 (Silice précipitée de chez Rhodia Silices) dont la granulométrie est dlO = 3,59 μm, d50 = 9,19 μm, d90 = 25,02 μm ;Tixosil 331 (precipitated silica from Rhodia Silices) whose particle size is d10 = 3.59 μm, d50 = 9.19 μm, d90 = 25.02 μm;
Tixosil 38 (Silice précipitée de chezTixosil 38 (Precipitated silica from
Rhodia Silices) dont la granulométrie est dlO = 1,40 μm, d50 = 3,66 μm, d90 = 8,79 μm. Les granulométries ont été déterminées par granulométrie laser.
V.l. Résultats de porosité accessible à l'eau.Rhodia Silica) whose particle size is d10 = 1.40 μm, d50 = 3.66 μm, d90 = 8.79 μm. The particle sizes were determined by laser granulometry. VI Results of porosity accessible to water.
Le tableau 3 ci-après compare les valeurs des porosités totales des géopolymères synthétisés avec les silices Tixosil 331 et 38 à la porosité d'un géopolymère synthétisé par une silice précipitée BDH.Table 3 below compares the values of the total porosities of the geopolymers synthesized with Tixosil silicas 331 and 38 to the porosity of a geopolymer synthesized by a BDH precipitated silica.
Le diamètre médian et l'étendue de la distribution granulométrique ont une influence importante sur la porosité accessible à l'eau : plus le diamètre médian est faible, plus la porosité totale est faible.The median diameter and the extent of the particle size distribution have a significant influence on the porosity accessible to water: the lower the median diameter, the lower the total porosity.
Tableau 3 : Influence de la granulométrie de la silice sur le porosité totale des géopolymèresTable 3: Influence of the granulometry of silica on the total porosity of geopolymers
Porosité totale erTotal porosity
SiliceSilica
Tixosil 331 \° o Tixosil 38 précipitée BDHTixosil 331 \ ° o Tixosil 38 precipitated BDH
K+ S=I, 2 e=10 47,5 39,4 27,3K + S = I, 2 e = 10 47.5 39.4 27.3
K+ s=l, 2 e=12 53, 6 42,3 36,3K + s = 1, 2 e = 12 53, 6 42.3 36.3
V.2. Résultats de distribution en taille des pores .V.2. Pore size distribution results.
Le tableau 4 récapitule les formulations des géopolymères étudiés.Table 4 summarizes the formulations of the geopolymers studied.
Tableau 4 : Formulation des géopolymères étudiésTable 4: Formulation of Geopolymers Studied
Formule Silice κ+ s=l, 2 e= 10 Tixosil 331 κ+ s=l, 2 e= 10 Tixosil 38 κ+ s=l, 2 e= 12 Tixosil 331 κ+ s=l, 2 e= 12 Tixosil 38
La distribution en taille des diamètres d'accès aux pores, obtenue par porosimétrie mercure, est reportée sur la figure 3.Formula Silica κ + s = 1, 2 e = 10 Tixosil 331 κ + s = 1, 2 e = 10 Tixosil 38 κ + s = 1, 2 e = 12 Tixosil 331 κ + s = 1, 2 e = 12 Tixosil 38 The size distribution of the pore access diameters, obtained by mercury porosimetry, is shown in FIG.
La silice Tixosil 38 permet d'obtenir des géopolymères dont la dispersion des pores est centrée autour de valeurs plus petites que la Tixosil 331. La silice Tixosil 38 possède une taille de grain légèrement inférieure à la Tixosil 331, mais surtout beaucoup moins dispersée. II est à souligner que la porosité obtenue est toujours mésoporeuse (teneur en silice), affinée (cation compensateur potassium) : la granulométrie de la silice influence donc essentiellement la porosité accessible à l'eau du matériau et les dimensions caractéristiques du diamètre sur lequel le mode poreux est centré.The silica Tixosil 38 makes it possible to obtain geopolymers whose pore dispersion is centered around values smaller than the Tixosil 331. The silica Tixosil 38 has a grain size slightly smaller than the Tixosil 331, but especially much less dispersed. It should be emphasized that the porosity obtained is always mesoporous (silica content), refined (potassium compensating cation): the grain size of the silica therefore essentially influences the water-accessible porosity of the material and the characteristic dimensions of the diameter on which the porous mode is centered.
ConclusionConclusion
Une formulation judicieuse des géopolymères permet de contrôler la macroporosité et/ou la mésoporosité de ces matériaux et ouvre la voie à une ingénierie de la porosité de ces matériaux, polymères inorganiques alumino-silicatés amorphes.A judicious formulation of the geopolymers makes it possible to control the macroporosity and / or the mesoporosity of these materials and opens the way to an engineering of the porosity of these materials, amorphous aluminosilicate inorganic polymers.
Les applications de ce type de matériaux faciles à mettre en œuvre, peu onéreux et dont les propriétés thermiques et de résistance au feu ne sont plus à démontrer, pourraient se montrer multiples dans des secteurs industriels variés utilisant des supports catalytiques et/ou de séparation d'espèces chimiques.
RéférencesThe applications of this type of easy-to-use, inexpensive materials whose thermal and fire resistance properties are no longer to be demonstrated, could be manifold in a variety of industrial sectors using catalytic supports and / or separation materials. 'chemical species. References
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Claims
REVENDICATIONS
1) Procédé de préparation d'un géopolymère à porosité contrôlée comprenant une étape de dissolution/polycondensation d'une source alumino- silicatée dans une solution d' activation pouvant éventuellement contenir des composants silicates, caractérisé en ce qu' il comprend les étapes successives suivantes consistant à a. définir au moins une caractéristique de la porosité du géopolymère à préparer ; b. déterminer une valeur ou un élément pour au moins un paramètre choisi parmi la quantité totale d'eau, la quantité totale de silice, le cation de compensation, et la distribution granulométrique des éventuels composants silicates, permettant d'obtenir la caractéristique définie à l'étape (a) ; c. sélectionner ladite valeur ou ledit élément pré-déterminé (e) à l'étape (b) .1) Process for the preparation of a geopolymer with controlled porosity comprising a step of dissolution / polycondensation of an aluminosilicate source in an activating solution that may optionally contain silicate components, characterized in that it comprises the following successive stages consisting of a. define at least one characteristic of the porosity of the geopolymer to be prepared; b. determining a value or an element for at least one parameter selected from the total amount of water, the total amount of silica, the compensation cation, and the particle size distribution of the possible silicate components, to obtain the characteristic defined in step (a); vs. select said value or said element predetermined in step (b).
2) Procédé de préparation selon la revendication 1, caractérisé en ce que ladite étape (c) consiste à sélectionner une valeur pré-déterminée pour la quantité totale d'eau et/ou pour la distribution granulométrique desdits composants silicates afin d'obtenir un géopolymère dont la porosité accessible à l'eau est comprise entre de l'ordre de 15 % et de l'ordre de 65 %.2) A method of preparation according to claim 1, characterized in that said step (c) consists in selecting a predetermined value for the total amount of water and / or for the particle size distribution of said silicate components in order to obtain a geopolymer whose porosity accessible to water is between about 15% and about 65%.
3) Procédé de préparation selon l'une quelconque des revendications 1 ou 2, caractérisé en ce
que la valeur pré-déterminée pour la distribution granulométrique desdits composants silicates est choisie parmi une valeur pré-déterminée du diamètre médian de la distribution granulométrique desdits composants silicates ou une valeur pré-déterminée de l'étendue de la distribution granulométrique desdits composants silicates.3) A method of preparation according to any one of claims 1 or 2, characterized in that that the predetermined value for the particle size distribution of said silicate components is selected from a predetermined value of the median diameter of the particle size distribution of said silicate components or a predetermined value of the extent of the particle size distribution of said silicate components.
4) Procédé de préparation selon l'une quelconque des revendications 1 à 3, caractérisé en ce que ladite étape de sélection consiste à sélectionner une valeur pré-déterminée pour la quantité totale de silice afin d'obtenir un géopolymère présentant une microporosité, mésoporosité ou macroporosité monomodale.4) A method of preparation according to any one of claims 1 to 3, characterized in that said selecting step comprises selecting a predetermined value for the total amount of silica to obtain a geopolymer having a microporosity, mesoporosity or monomodal macroporosity.
5) Procédé de préparation selon l'une quelconque des revendications 1 à 4, caractérisé en ce que la sélection d'une quantité totale de silice avec un rapport molaire Siθ2/M2O supérieur à 1 permet d'obtenir un géopolymère présentant une mésoporosité monomodale, M2O représentant la quantité molaire d'oxyde de cations de compensation dans la solution d' activation .5) Preparation process according to any one of claims 1 to 4, characterized in that the selection of a total amount of silica with a SiO 2 / M 2 O molar ratio greater than 1 makes it possible to obtain a geopolymer having a mesoporosity monomodal, M 2 O representing the molar amount of compensation cation oxide in the activation solution.
6) Procédé de préparation selon l'une quelconque des revendications 1 à 4, caractérisé en ce que la sélection d'une quantité totale de silice avec un rapport molaire SiO2ZM2O inférieur à 1 permet d'obtenir un géopolymère présentant une macroporosité monomodale, M2O représentant la quantité molaire
d'oxyde de cations de compensation dans la solution d' activation .6) Preparation process according to any one of claims 1 to 4, characterized in that the selection of a total amount of silica with a SiO 2 ZM 2 O molar ratio of less than 1 makes it possible to obtain a geopolymer having a macroporosity monomodal, M 2 O representing the molar amount compensation cation oxide in the activating solution.
7) Procédé de préparation selon l'une quelconque des revendications précédentes, caractérisé en ce que l'étape de sélection consiste à sélectionner ledit cation de compensation parmi les métaux alcalins, les métaux alcalino-terreux et leurs mélanges.7) Preparation process according to any one of the preceding claims, characterized in that the selection step comprises selecting said cation of compensation among alkali metals, alkaline earth metals and mixtures thereof.
8) Procédé de préparation selon l'une quelconque des revendications précédentes, caractérisé en ce que l'étape de sélection consiste à sélectionner un cation de compensation parmi le potassium, le sodium et le césium pour obtenir une distribution porale du géopolymère contenant comme cation de compensation du potassium, inférieure à la distribution porale du géopolymère contenant comme cation de compensation du sodium, elle-même inférieure à la distribution porale du géopolymère contenant comme cation de compensation du césium.8) Preparation process according to any one of the preceding claims, characterized in that the selection step consists in selecting a compensation cation among potassium, sodium and cesium to obtain a poral distribution of the geopolymer containing as cation of potassium compensation, lower than the pore distribution of the geopolymer containing sodium compensation cation, itself lower than the pore distribution of the geopolymer containing as cesium compensation cation.
9) Procédé de préparation selon l'une quelconque des revendications précédentes, caractérisé en ce que ladite source alumino-silicatée est une source solide contenant des alumino-silicates amorphes.9) Preparation process according to any one of the preceding claims, characterized in that said alumino-silicate source is a solid source containing amorphous aluminosilicates.
10) Procédé de préparation selon la revendication 9, caractérisé en ce que lesdits alumino- silicates amorphes sont choisis parmi les minéraux d' alumino-silicates naturels, des minéraux d' alumino- silicates naturels calcinés, des verres synthétiques à
base d' alumino-silicates purs, du ciment alumineux, de la ponce, des sous-produits calcinés ou résidus d'exploitation industrielle et des mélanges de ceux-ci.10) Preparation process according to claim 9, characterized in that said amorphous aluminosilicates are chosen from natural alumino-silicate minerals, calcined natural aluminosilicate minerals, synthetic base of pure aluminosilicates, aluminous cement, pumice, calcined by-products or industrial residues and mixtures thereof.
11) Procédé de préparation selon l'une quelconque des revendications précédentes, caractérisé en ce que ladite solution d' activation est une solution aqueuse fortement alcaline pouvant éventuellement contenir des composants silicates.11) Preparation process according to any one of the preceding claims, characterized in that said activation solution is a strongly alkaline aqueous solution which may optionally contain silicate components.
12) Procédé de préparation selon l'une quelconque des revendications précédentes, caractérisé en ce que lesdits composants silicates sont :12) Preparation process according to any one of the preceding claims, characterized in that said silicate components are:
- le ou le (s) silicate (s) apporté (s) sous forme de silicates des cations de compensation, le ou les silicate (s) ajouté (s) et choisi (s) parmi la silice, la silice colloïdale et la silice vitreuse un mélange de ces deux sources de silicates.the silicate (s) provided in the form of silicate (s) of the compensation cations, the silicate (s) added (s) and chosen from silica, colloidal silica and silica; vitreous a mixture of these two sources of silicates.
13) Procédé de préparation selon l'une quelconque des revendications précédentes, caractérisé en ce que ladite solution d' activation présente un pH supérieur à 9.13) Preparation process according to any one of the preceding claims, characterized in that said activation solution has a pH greater than 9.
14) Géopolymère susceptible d'être préparé par un procédé tel que défini dans l'une quelconque des revendications précédentes, caractérisé en ce que ledit géopolymère présente une mésoporosité monomodale avec 50% des pores présentant un diamètre d'accessibilité
déterminé par porosité mercure s' étendant sur moins de 5 nm (répartition porale fortement affinée) ou entre 5 et 10 nm (répartition porale plus large) .14) Geopolymer capable of being prepared by a process as defined in any one of the preceding claims, characterized in that said geopolymer has a monomodal mesoporosity with 50% of the pores having an accessibility diameter. determined by mercury porosity extending over less than 5 nm (highly refined poral distribution) or between 5 and 10 nm (wider pore distribution).
15) Géopolymère susceptible d'être préparé par un procédé tel que défini dans l'une quelconque des revendications 1 à 13, caractérisé en ce que ledit géopolymère présente une macroporosité monomodale avec 50% des pores présentant un diamètre d'accessibilité déterminé par porosité mercure s' étendant sur moins de 10 nm (répartition porale fortement affinée) ou entre 10 et 50 nm (répartition porale plus large) .15) Geopolymer capable of being prepared by a process as defined in any one of claims 1 to 13, characterized in that said geopolymer has a monomodal macroporosity with 50% of the pores having an accessibility diameter determined by mercury porosity extending over less than 10 nm (highly refined pore distribution) or between 10 and 50 nm (wider pore distribution).
16) Support catalytique et/ou de séparation d'espèces chimiques comprenant un géopolymère selon l'une quelconque des revendications 14 ou 15.16) catalytic carrier and / or chemical species separation comprising a geopolymer according to any one of claims 14 or 15.
17) Utilisation d'un géopolymère selon l'une quelconque des revendications 14 ou 15 en catalyse.17) Use of a geopolymer according to any one of claims 14 or 15 in catalysis.
18) Utilisation d'un géopolymère selon l'une quelconque des revendications 14 ou 15 en filtration .
18) Use of a geopolymer according to any one of claims 14 or 15 in filtration.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR0758409A FR2922543B1 (en) | 2007-10-18 | 2007-10-18 | PROCESS FOR THE PREPARATION OF A CONTROLLED POROSITY-BASED GEOPOLYMER, THE GEOPOLYMER THUS OBTAINED AND ITS DIFFERENT APPLICATIONS |
| PCT/EP2008/063865 WO2009050196A1 (en) | 2007-10-18 | 2008-10-15 | Method of preparing a controlled porosity geopolymer, the resulting geopolymer and the various applications thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| EP2203385A1 true EP2203385A1 (en) | 2010-07-07 |
Family
ID=39433965
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP08839022A Ceased EP2203385A1 (en) | 2007-10-18 | 2008-10-15 | Method of preparing a controlled porosity geopolymer, the resulting geopolymer and the various applications thereof |
Country Status (8)
| Country | Link |
|---|---|
| US (1) | US20100222204A1 (en) |
| EP (1) | EP2203385A1 (en) |
| JP (1) | JP2011500494A (en) |
| KR (1) | KR20100085112A (en) |
| CN (1) | CN101827786A (en) |
| FR (1) | FR2922543B1 (en) |
| RU (1) | RU2503617C2 (en) |
| WO (1) | WO2009050196A1 (en) |
Families Citing this family (22)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011062689A (en) * | 2009-08-17 | 2011-03-31 | Toshiyuki Takahashi | Method of decomposing and deodorizing sludge odor using metal oxide mixed composition and method of decomposing sludge |
| WO2011046910A2 (en) | 2009-10-14 | 2011-04-21 | Arizona Board Of Regents For And On Behalf Of Arizona State University | Fabricating porous materials using thixotropic gels |
| US9242900B2 (en) | 2009-12-01 | 2016-01-26 | Arizona Board Of Regents, A Body Corporate Of The State Of Arizona Acting For And On Behalf Of Arizona State University | Porous geopolymer materials |
| US9365691B2 (en) | 2010-08-06 | 2016-06-14 | Arizona Board Of Regents, A Body Corporate Of The State Of Arizona Acting For And On Behalf Of Arizona State University | Fabricating porous materials using intrepenetrating inorganic-organic composite gels |
| KR101078335B1 (en) | 2011-06-01 | 2011-11-01 | 주식회사 영일화성 | Process of producing geopolymer using sodium silicate and the geopolymer |
| KR102060844B1 (en) | 2011-09-21 | 2019-12-30 | 아리조나 보드 오브 리전트스, 아리조나주의 아리조나 주립대 대행법인 | Geopolymer resin materials, geopolymer materials, and materials produced thereby |
| KR101140102B1 (en) * | 2012-01-26 | 2012-04-30 | 천용승 | Method for repairing section of progressive concrete structure using eco-friendly geopolymer mortar |
| JP6210659B2 (en) * | 2012-08-01 | 2017-10-11 | 国立大学法人京都大学 | Treatment method for cesium-containing waste. |
| US10170759B2 (en) | 2013-06-21 | 2019-01-01 | Arizona Board Of Regents On Behalf Of Arizona State University | Metal oxides from acidic solutions |
| EP2853567A1 (en) * | 2013-09-27 | 2015-04-01 | Heraeus Precious Metals GmbH & Co. KG | Solar cells produced from high ohmic wafers and paste comprising Ag metal-oxide additive |
| FR3019176A1 (en) * | 2014-03-27 | 2015-10-02 | Commissariat Energie Atomique | PROCESS FOR THE PREPARATION OF A MACROPOROUS AND MESOPOROUS GEOPOLYMER WITH CONTROLLED POROSITY |
| CA2951879A1 (en) * | 2014-06-12 | 2015-12-17 | Arizona Board Of Regents On Behalf Of Arizona State University | Geopolymer aggregates |
| US10926241B2 (en) | 2014-06-12 | 2021-02-23 | Arizona Board Of Regents On Behalf Of Arizona State University | Carbon dioxide adsorbents |
| JP6895887B2 (en) * | 2014-12-30 | 2021-06-30 | エボニック オペレーションズ ゲーエムベーハー | Aluminosilicates and coatings made from aluminosilicates for VOC removal |
| JP6664639B2 (en) * | 2016-02-26 | 2020-03-13 | アドバンエンジ株式会社 | Radiation shield |
| JP6761682B2 (en) * | 2016-06-30 | 2020-09-30 | 大和ハウス工業株式会社 | Method for manufacturing silicate polymer molded product |
| US10829382B2 (en) | 2017-01-20 | 2020-11-10 | Skysong Innovations | Aluminosilicate nanorods |
| JP6990815B2 (en) * | 2017-08-25 | 2022-01-12 | 久幸 末松 | Hydrogen recombination catalyst |
| CN111135796B (en) * | 2020-01-09 | 2022-02-11 | 常熟理工学院 | Strong-effect geopolymerization defluorinating agent and preparation method and application thereof |
| FR3106507B1 (en) * | 2020-01-28 | 2024-03-01 | Commissariat Energie Atomique | SOLID MATERIAL WITH MULTIPLE OPEN POROSITY COMPRISING A GEOPOLYMER AND SOLID PARTICLES AND PREPARATION METHOD THEREFOR |
| CN111320425A (en) * | 2020-02-29 | 2020-06-23 | 运城学院 | Coal ash geopolymer/g-C3N4Composite catalyst and preparation method thereof |
| CN114377662A (en) * | 2022-03-03 | 2022-04-22 | 华北理工大学 | Steel slag-based porous geopolymer adsorption material and preparation method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20060251909A1 (en) * | 2005-05-09 | 2006-11-09 | Beall George H | Geopolymer composites and structures formed therefrom |
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| US4859367A (en) * | 1987-10-02 | 1989-08-22 | Joseph Davidovits | Waste solidification and disposal method |
| FR2666253B1 (en) * | 1990-09-04 | 1992-10-30 | Davidovits Joseph | PROCESS FOR OBTAINING A GEOPOLYMERIC BINDER FOR STABILIZATION, SOLIDIFICATION AND CONSOLIDATION OF TOXIC WASTE. |
| DE69406655T2 (en) * | 1994-07-08 | 1998-03-26 | Tosoh Corp | Amorphous aluminosilicate and process for its manufacture |
| DE19841740A1 (en) * | 1998-09-09 | 2000-03-16 | Porzellanwerk Kloster Veilsdor | Ceramic catalyst for the selective decomposition of N2O and process for its production |
| US7141112B2 (en) * | 2003-01-31 | 2006-11-28 | Douglas C Comrie | Cementitious materials including stainless steel slag and geopolymers |
| FR2872151B1 (en) * | 2004-06-24 | 2007-06-29 | Inst Francais Du Petrole | MATERIAL ALUMINOSILICATE MESOSTRUCTURE |
| CN102352274B (en) * | 2005-03-17 | 2015-01-21 | Noxii国际有限公司 | Sorbent compositions and method of using the sorbent compositions to reduce mercury emissions from the burning of coal |
-
2007
- 2007-10-18 FR FR0758409A patent/FR2922543B1/en active Active
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2008
- 2008-10-15 US US12/738,590 patent/US20100222204A1/en not_active Abandoned
- 2008-10-15 JP JP2010529367A patent/JP2011500494A/en active Pending
- 2008-10-15 EP EP08839022A patent/EP2203385A1/en not_active Ceased
- 2008-10-15 KR KR1020107010839A patent/KR20100085112A/en not_active Application Discontinuation
- 2008-10-15 CN CN200880112156A patent/CN101827786A/en active Pending
- 2008-10-15 WO PCT/EP2008/063865 patent/WO2009050196A1/en active Application Filing
- 2008-10-15 RU RU2010119693/04A patent/RU2503617C2/en not_active IP Right Cessation
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20060251909A1 (en) * | 2005-05-09 | 2006-11-09 | Beall George H | Geopolymer composites and structures formed therefrom |
Also Published As
| Publication number | Publication date |
|---|---|
| US20100222204A1 (en) | 2010-09-02 |
| RU2010119693A (en) | 2011-11-27 |
| CN101827786A (en) | 2010-09-08 |
| WO2009050196A1 (en) | 2009-04-23 |
| FR2922543A1 (en) | 2009-04-24 |
| JP2011500494A (en) | 2011-01-06 |
| RU2503617C2 (en) | 2014-01-10 |
| FR2922543B1 (en) | 2011-10-14 |
| KR20100085112A (en) | 2010-07-28 |
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