CN112264085B - Solid base catalyst KF/Mg-Al-LDO/MCM-41 and preparation method and application thereof - Google Patents
Solid base catalyst KF/Mg-Al-LDO/MCM-41 and preparation method and application thereof Download PDFInfo
- Publication number
- CN112264085B CN112264085B CN202011319446.2A CN202011319446A CN112264085B CN 112264085 B CN112264085 B CN 112264085B CN 202011319446 A CN202011319446 A CN 202011319446A CN 112264085 B CN112264085 B CN 112264085B
- Authority
- CN
- China
- Prior art keywords
- mcm
- solution
- ldo
- catalyst
- metal salt
- 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.)
- Active
Links
- 239000003054 catalyst Substances 0.000 title claims abstract description 92
- 238000002360 preparation method Methods 0.000 title claims abstract description 27
- 239000007787 solid Substances 0.000 title claims abstract description 24
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 title claims abstract description 17
- 239000003225 biodiesel Substances 0.000 claims abstract description 53
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims abstract description 51
- 239000002253 acid Substances 0.000 claims abstract description 38
- 238000001035 drying Methods 0.000 claims abstract description 28
- 229910052751 metal Inorganic materials 0.000 claims abstract description 28
- 150000003839 salts Chemical class 0.000 claims abstract description 28
- 239000002184 metal Substances 0.000 claims abstract description 27
- 239000002808 molecular sieve Substances 0.000 claims abstract description 26
- URGAHOPLAPQHLN-UHFFFAOYSA-N sodium aluminosilicate Chemical compound [Na+].[Al+3].[O-][Si]([O-])=O.[O-][Si]([O-])=O URGAHOPLAPQHLN-UHFFFAOYSA-N 0.000 claims abstract description 26
- 238000003756 stirring Methods 0.000 claims abstract description 21
- 238000006243 chemical reaction Methods 0.000 claims abstract description 20
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 19
- LZZYPRNAOMGNLH-UHFFFAOYSA-M Cetrimonium bromide Chemical compound [Br-].CCCCCCCCCCCCCCCC[N+](C)(C)C LZZYPRNAOMGNLH-UHFFFAOYSA-M 0.000 claims abstract description 15
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 15
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 15
- 239000010703 silicon Substances 0.000 claims abstract description 15
- 238000001914 filtration Methods 0.000 claims abstract description 13
- 238000001354 calcination Methods 0.000 claims abstract description 10
- 238000002156 mixing Methods 0.000 claims abstract description 10
- 238000007598 dipping method Methods 0.000 claims abstract description 9
- 238000002791 soaking Methods 0.000 claims abstract description 9
- 238000005216 hydrothermal crystallization Methods 0.000 claims abstract description 8
- 230000032683 aging Effects 0.000 claims abstract description 7
- 239000000377 silicon dioxide Substances 0.000 claims abstract description 6
- 239000000243 solution Substances 0.000 claims description 84
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims description 39
- 239000003921 oil Substances 0.000 claims description 27
- 241001048891 Jatropha curcas Species 0.000 claims description 26
- 235000019198 oils Nutrition 0.000 claims description 26
- 238000000034 method Methods 0.000 claims description 23
- 239000002585 base Substances 0.000 claims description 18
- 235000015112 vegetable and seed oil Nutrition 0.000 claims description 18
- 239000002244 precipitate Substances 0.000 claims description 17
- VSCWAEJMTAWNJL-UHFFFAOYSA-K aluminium trichloride Chemical group Cl[Al](Cl)Cl VSCWAEJMTAWNJL-UHFFFAOYSA-K 0.000 claims description 16
- 239000000203 mixture Substances 0.000 claims description 14
- 239000000047 product Substances 0.000 claims description 14
- 238000005470 impregnation Methods 0.000 claims description 12
- 239000007788 liquid Substances 0.000 claims description 11
- 239000003513 alkali Substances 0.000 claims description 10
- 238000005406 washing Methods 0.000 claims description 10
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 claims description 9
- 235000011114 ammonium hydroxide Nutrition 0.000 claims description 9
- 239000003795 chemical substances by application Substances 0.000 claims description 9
- 239000008367 deionised water Substances 0.000 claims description 8
- 229910021641 deionized water Inorganic materials 0.000 claims description 8
- 229910021642 ultra pure water Inorganic materials 0.000 claims description 8
- 239000012498 ultrapure water Substances 0.000 claims description 8
- 238000000967 suction filtration Methods 0.000 claims description 7
- 238000002425 crystallisation Methods 0.000 claims description 6
- 230000008025 crystallization Effects 0.000 claims description 6
- 230000008569 process Effects 0.000 claims description 6
- 239000012266 salt solution Substances 0.000 claims description 6
- 238000009210 therapy by ultrasound Methods 0.000 claims description 6
- TWRXJAOTZQYOKJ-UHFFFAOYSA-L Magnesium chloride Chemical compound [Mg+2].[Cl-].[Cl-] TWRXJAOTZQYOKJ-UHFFFAOYSA-L 0.000 claims description 4
- 230000007935 neutral effect Effects 0.000 claims description 4
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 claims description 3
- 238000002390 rotary evaporation Methods 0.000 claims description 3
- 229910001629 magnesium chloride Inorganic materials 0.000 claims description 2
- 238000000926 separation method Methods 0.000 abstract description 4
- 230000000694 effects Effects 0.000 abstract description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 21
- 239000011777 magnesium Substances 0.000 description 17
- 239000011148 porous material Substances 0.000 description 16
- 230000000052 comparative effect Effects 0.000 description 15
- 239000010410 layer Substances 0.000 description 14
- 238000005303 weighing Methods 0.000 description 13
- GDVKFRBCXAPAQJ-UHFFFAOYSA-A dialuminum;hexamagnesium;carbonate;hexadecahydroxide Chemical compound [OH-].[OH-].[OH-].[OH-].[OH-].[OH-].[OH-].[OH-].[OH-].[OH-].[OH-].[OH-].[OH-].[OH-].[OH-].[OH-].[Mg+2].[Mg+2].[Mg+2].[Mg+2].[Mg+2].[Mg+2].[Al+3].[Al+3].[O-]C([O-])=O GDVKFRBCXAPAQJ-UHFFFAOYSA-A 0.000 description 10
- 229910001701 hydrotalcite Inorganic materials 0.000 description 10
- 229960001545 hydrotalcite Drugs 0.000 description 10
- 230000003197 catalytic effect Effects 0.000 description 7
- 230000009467 reduction Effects 0.000 description 7
- 238000000975 co-precipitation Methods 0.000 description 6
- 239000002131 composite material Substances 0.000 description 6
- 150000002148 esters Chemical group 0.000 description 6
- 238000003837 high-temperature calcination Methods 0.000 description 6
- 229910044991 metal oxide Inorganic materials 0.000 description 6
- 150000004706 metal oxides Chemical class 0.000 description 6
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 description 5
- 239000012071 phase Substances 0.000 description 5
- 238000011161 development Methods 0.000 description 4
- 230000018109 developmental process Effects 0.000 description 4
- 235000021588 free fatty acids Nutrition 0.000 description 4
- 239000011229 interlayer Substances 0.000 description 4
- 238000011068 loading method Methods 0.000 description 4
- VLKZOEOYAKHREP-UHFFFAOYSA-N n-Hexane Chemical compound CCCCCC VLKZOEOYAKHREP-UHFFFAOYSA-N 0.000 description 4
- 239000003208 petroleum Substances 0.000 description 4
- 238000011160 research Methods 0.000 description 4
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 3
- 230000002776 aggregation Effects 0.000 description 3
- SNAAJJQQZSMGQD-UHFFFAOYSA-N aluminum magnesium Chemical compound [Mg].[Al] SNAAJJQQZSMGQD-UHFFFAOYSA-N 0.000 description 3
- WPYMKLBDIGXBTP-UHFFFAOYSA-N benzoic acid Chemical compound OC(=O)C1=CC=CC=C1 WPYMKLBDIGXBTP-UHFFFAOYSA-N 0.000 description 3
- 238000006555 catalytic reaction Methods 0.000 description 3
- 238000003760 magnetic stirring Methods 0.000 description 3
- 238000005809 transesterification reaction Methods 0.000 description 3
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 2
- 102000004190 Enzymes Human genes 0.000 description 2
- 108090000790 Enzymes Proteins 0.000 description 2
- 238000005054 agglomeration Methods 0.000 description 2
- 229960000892 attapulgite Drugs 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 239000000706 filtrate Substances 0.000 description 2
- 238000005242 forging Methods 0.000 description 2
- 235000011187 glycerol Nutrition 0.000 description 2
- 238000007210 heterogeneous catalysis Methods 0.000 description 2
- 238000007172 homogeneous catalysis Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 229910052625 palygorskite Inorganic materials 0.000 description 2
- KJFMBFZCATUALV-UHFFFAOYSA-N phenolphthalein Chemical compound C1=CC(O)=CC=C1C1(C=2C=CC(O)=CC=2)C2=CC=CC=C2C(=O)O1 KJFMBFZCATUALV-UHFFFAOYSA-N 0.000 description 2
- 238000000746 purification Methods 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 230000035484 reaction time Effects 0.000 description 2
- 238000007127 saponification reaction Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 239000008158 vegetable oil Substances 0.000 description 2
- 239000002699 waste material Substances 0.000 description 2
- LXQOQPGNCGEELI-UHFFFAOYSA-N 2,4-dinitroaniline Chemical compound NC1=CC=C([N+]([O-])=O)C=C1[N+]([O-])=O LXQOQPGNCGEELI-UHFFFAOYSA-N 0.000 description 1
- ZPLCXHWYPWVJDL-UHFFFAOYSA-N 4-[(4-hydroxyphenyl)methyl]-1,3-oxazolidin-2-one Chemical compound C1=CC(O)=CC=C1CC1NC(=O)OC1 ZPLCXHWYPWVJDL-UHFFFAOYSA-N 0.000 description 1
- TYMLOMAKGOJONV-UHFFFAOYSA-N 4-nitroaniline Chemical compound NC1=CC=C([N+]([O-])=O)C=C1 TYMLOMAKGOJONV-UHFFFAOYSA-N 0.000 description 1
- 239000005711 Benzoic acid Substances 0.000 description 1
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 1
- 241001465754 Metazoa Species 0.000 description 1
- ULGYAEQHFNJYML-UHFFFAOYSA-N [AlH3].[Ca] Chemical compound [AlH3].[Ca] ULGYAEQHFNJYML-UHFFFAOYSA-N 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 239000004480 active ingredient Substances 0.000 description 1
- 239000003463 adsorbent Substances 0.000 description 1
- 238000004220 aggregation Methods 0.000 description 1
- HZVVJJIYJKGMFL-UHFFFAOYSA-N almasilate Chemical compound O.[Mg+2].[Al+3].[Al+3].O[Si](O)=O.O[Si](O)=O HZVVJJIYJKGMFL-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910001579 aluminosilicate mineral Inorganic materials 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 239000010775 animal oil Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 235000010233 benzoic acid Nutrition 0.000 description 1
- CNLSPQQMAJCIFB-UHFFFAOYSA-N benzoic acid;ethanol Chemical compound CCO.OC(=O)C1=CC=CC=C1 CNLSPQQMAJCIFB-UHFFFAOYSA-N 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 150000001768 cations Chemical class 0.000 description 1
- 238000005119 centrifugation Methods 0.000 description 1
- 238000012512 characterization method Methods 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 239000004927 clay Substances 0.000 description 1
- 239000003245 coal Substances 0.000 description 1
- 229910052681 coesite Inorganic materials 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 229910052906 cristobalite Inorganic materials 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- CRPOUZQWHJYTMS-UHFFFAOYSA-N dialuminum;magnesium;disilicate Chemical compound [Mg+2].[Al+3].[Al+3].[O-][Si]([O-])([O-])[O-].[O-][Si]([O-])([O-])[O-] CRPOUZQWHJYTMS-UHFFFAOYSA-N 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000004817 gas chromatography Methods 0.000 description 1
- 239000004519 grease Substances 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 229910003471 inorganic composite material Inorganic materials 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000005342 ion exchange Methods 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 238000011031 large-scale manufacturing process Methods 0.000 description 1
- 230000001050 lubricating effect Effects 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000011259 mixed solution Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 239000000178 monomer Substances 0.000 description 1
- 239000004006 olive oil Substances 0.000 description 1
- 235000008390 olive oil Nutrition 0.000 description 1
- 239000012074 organic phase Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 239000008188 pellet Substances 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 239000000376 reactant Substances 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 235000012424 soybean oil Nutrition 0.000 description 1
- 239000003549 soybean oil Substances 0.000 description 1
- 229910052682 stishovite Inorganic materials 0.000 description 1
- 238000004448 titration Methods 0.000 description 1
- 229910052905 tridymite Inorganic materials 0.000 description 1
Images
Classifications
-
- 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
- B01J29/00—Catalysts comprising molecular sieves
- B01J29/04—Catalysts comprising molecular sieves having base-exchange properties, e.g. crystalline zeolites
- B01J29/041—Mesoporous materials having base exchange properties, e.g. Si/Al-MCM-41
-
- 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
- B01J35/61—Surface area
-
- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
- C10G3/00—Production of liquid hydrocarbon mixtures from oxygen-containing organic materials, e.g. fatty oils, fatty acids
- C10G3/42—Catalytic treatment
- C10G3/44—Catalytic treatment characterised by the catalyst used
- C10G3/48—Catalytic treatment characterised by the catalyst used further characterised by the catalyst support
- C10G3/49—Catalytic treatment characterised by the catalyst used further characterised by the catalyst support containing crystalline aluminosilicates, e.g. molecular sieves
-
- 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
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E50/00—Technologies for the production of fuel of non-fossil origin
- Y02E50/10—Biofuels, e.g. bio-diesel
-
- 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
- Y02P30/00—Technologies relating to oil refining and petrochemical industry
- Y02P30/20—Technologies relating to oil refining and petrochemical industry using bio-feedstock
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Chemistry (AREA)
- Crystallography & Structural Chemistry (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Materials Engineering (AREA)
- General Chemical & Material Sciences (AREA)
- Dispersion Chemistry (AREA)
- Catalysts (AREA)
Abstract
The invention discloses a solid base catalyst KF/Mg-Al-LDO/MCM-41 and a preparation method and application thereof, wherein the preparation of the catalyst comprises the following steps: mixing and dispersing ATP in HCl solution, and filtering after soaking; adding acid modified ATP into NaOH solution, adding CTAB solution, stirring, performing hydrothermal crystallization, and calcining at high temperature to obtain MCM-41 mesoporous silica molecular sieve; taking divalent metal salt and trivalent metal salt to be ultrasonically mixed with the MCM-41 mesoporous silicon molecular sieve, standing, aging, and calcining at high temperature to obtain LDO/MCM-41; adding LDO/MCM-41 into KF solution, dipping, drying and roasting at high temperature to obtain the solid base catalyst. The catalyst prepared by the invention has the advantages of high reaction activity, rich alkaline sites, good acid and water resistance, easy separation and repeated use, and can be effectively applied to the preparation of biodiesel.
Description
Technical Field
The invention relates to a solid base catalyst, in particular to a solid base catalyst KF/Mg-Al-LDO/MCM-41 and a preparation method and application thereof.
Background
With the rapid development of the human economic society and the increasing demand of energy, the total amount of non-renewable energy sources such as petroleum, coal and the like is gradually reduced, and the environmental pollution generated in the use process of fossil energy is increasingly prominent, which prompts the human to continuously develop and research novel clean renewable energy sources.
The biodiesel is prepared by using animal and vegetable oil, waste catering oil and the like as raw material oil and short-chain alcohol (methanol or ethanol) through ester exchange reaction. The catalyst can replace petroleum, has the characteristics of high flash point, good lubricating property, reproducibility, environmental friendliness and the like, and becomes a hot point of current scientific research, so that the development of the catalyst has low cost, environmental protection and high catalytic efficiency, and the realization of large-scale production becomes a difficult problem which is urgently needed to be solved at present. At present, homogeneous catalysis, heterogeneous catalysis, enzyme catalysis and the like can be used for the preparation method of the biodiesel. Compared with homogeneous catalysis and enzyme catalysis, heterogeneous catalysis has the advantages of easy separation of product, high catalysis efficiency, less waste liquid, less corrosion to equipment, high reusability, etc. and is widely used in biodiesel preparation.
Attapulgite clay (ATP) is a natural layer chain-shaped magnesium aluminosilicate mineral, and has large specific surface area, abundant surface charge and strong ion exchange capacity. Due to the rod-shaped crystal structure, rich nanopores and good adsorbability, the catalyst is widely applied to the fields of catalysts, adsorbents and the like. High content of natural ATP impurities and SiO2The percentage content is general, after acid modification, Mg between ATP layers2+、Fe3+、Ca2+When the cations are converted into soluble salts of corresponding acids to be dissolved out, the original interlayer binding force is weakened, the interlayer crystal lattice is cracked, the interlayer spacing is increased, a brand new active structure is formed, and the SiO is treated by the acid2The percentage content is greatly improved, and the specific surface area and the adsorption capacity are both obviously improved.
Hydrotalcite or hydrotalcite-like compounds (LDHs) are common Layered inorganic composite materials composed of divalent and trivalent metal elements, and are generally prepared by adding corresponding divalent and trivalent metal salts under alkaline conditions and performing coprecipitation.
Disclosure of Invention
The purpose of the invention is as follows: aiming at the problems in the prior art, the invention provides a preparation method of a novel solid base catalyst KF/Mg-Al-LDO/MCM-41 for biodiesel. Because ATP is low in price and rich in reserves, ATP is a silicon source of a relatively ideal mesoporous silicon molecular sieve, the production cost is reduced, and the product quality is improved.
The invention also provides a solid base catalyst KF/Mg-Al-LDO/MCM-41 and application thereof.
The technical scheme is as follows: in order to achieve the above object, the present invention provides a method for preparing a solid base catalyst KF/Mg-Al-LDO/MCM-41, comprising the steps of:
(1) mixing and dispersing ATP in HCl solution, soaking, filtering, and drying filter residue to obtain acid modified ATP;
(2) adding acid modified ATP into NaOH solution, adding CTAB solution under stirring, carrying out hydrothermal crystallization after stirring, washing and drying the obtained product, and calcining at high temperature to obtain the MCM-41 mesoporous silicon molecular sieve;
(3) adding a divalent metal salt and a trivalent metal salt into ultrapure water, stirring to prepare a uniformly dispersed salt solution A, adding the MCM-41 mesoporous silica molecular sieve prepared in the step (2) into the ultrapure water, stirring to form a dispersed solution B, ultrasonically mixing the solution A and the solution B, stirring, slowly dropwise adding an ammonia water solution, standing and aging the mixed sol after dropwise adding is finished, filtering, drying to obtain a white precipitate, and calcining the white precipitate at a high temperature to obtain the LDO/MCM-41;
(4) and (3) adding the LDO/MCM-41 into a KF solution by adopting an isometric impregnation method, drying and roasting at high temperature after impregnation, and obtaining the biodiesel catalyst KF/LDO/MCM-41.
Wherein, the concentration of the HCl solution in the step (1) is 1-3mol/L, the solid-to-liquid ratio of ATP to the HCl solution is 1:5-15g/mL, the mixture is soaked for 24 hours at 80 ℃, and filter residue is dried for 3 hours at 100 ℃ after suction filtration.
Preferably, after soaking, connecting a Buchner funnel with a vacuum suction filter for suction filtration, and drying filter residues to obtain the acid modified ATP.
Preferably, in the step (1), the concentration of the HCl solution is 2mol/L, and the solid-to-liquid ratio is 1:10 g/mL.
Wherein, in the step (2), the concentration of the NaOH solution is 0.2-0.6mol/L, the concentration of the CTAB solution is 5-15% g/mL, and the solid-to-liquid ratio of the acid modified ATP to the NaOH solution is 1:5-10 g/mL.
Wherein, the hydrothermal crystallization in the step (2) is crystallization at the temperature of 90-120 ℃ for 48-96h, and the crystallization is carried out at the high temperature of 400-800 ℃ for 2-5h after being washed and dried to remove the template agent CTAB.
Preferably, in the step (2), the concentration of the NaOH solution is 0.4mol/L, the concentration of the CTAB solution is 10%, the solid-to-liquid ratio of the acid modified ATP to the NaOH solution is 1:8g/mL, the solution is crystallized at the temperature of 110 ℃ for 72h, and the solution is calcined at the high temperature of 500 ℃ for 3h to remove the template agent, so that the MCM-41 mesoporous silica molecular sieve is obtained.
Wherein the divalent metal salt in the step (3) is MgCl2·6H2O, trivalent metal salt is AlCl3·6H2O, wherein the divalent metal salt and the trivalent metal salt are used in a molar ratio n (Mg)2+)、n(Al3+) Is represented by n (Mg)2+):n(Al3+) Is 1-5: 1.
Wherein the mass of the MCM-41 and the divalent metal salt and the trivalent metal salt in the step (3) are expressed by m (MCM-41) and m (LDH), and m (LDH) is 1-3: 1.
Wherein, in the step (3), the ultrasonic treatment is carried out for 30-60min under the condition of the power of 200-300W and the frequency of 50Hz, ammonia water solution with the concentration of 0.5-1mol/L is dripped until the solution is colloidal, the pH value is kept at 10-11 in the dripping process, the mixed sol is kept standing and aging for 6-18h at the temperature of 60-90 ℃, and the filtered and dried white precipitate is roasted for 3-6h at the temperature of 400-800 ℃ in a muffle furnace.
Preferably, n (Mg) in the step (4)2+):n(Al3+) The ratio of m (MCM-41) to m (LDH) is 3:1, the mixture is subjected to ultrasonic treatment for 40min, crystallized at 80 ℃ for 18h, and roasted at 600 ℃ for 4h to obtain Mg-Al-LDO/MCM-41.
Wherein the KF solution in the step (4) is 10-30 wt%, and the ratio of the catalyst LDO/MCM-41 to the KF solution in the equal-volume impregnation method is 1:1.3-1.5 g/mL; in the step (4), the dipping temperature is 30 ℃, the dipping time is 12-24h, and the dried product is roasted at 400-800 ℃ for 3-6 h.
Preferably, the KF loading in the step (4) is 15 wt%, the soaking time is 16h, and the KF/Mg-Al-LDO/MCM-41 is obtained by high-temperature roasting at 600 ℃ for 3h after drying.
The solid base catalyst KF/Mg-Al-LDO/MCM-41 prepared by the preparation method of the solid base catalyst KF/Mg-Al-LDO/MCM-41 is provided.
The solid base catalyst KF/Mg-Al-LDO/MCM-41 prepared by the preparation method of the solid base catalyst KF/Mg-Al-LDO/MCM-41 is applied to the preparation process of biodiesel.
The specific process of the application is as follows:
taking the barbadosnut oil subjected to the acid reduction treatment, controlling the molar ratio of methanol to the barbadosnut oil to be 10:1, adding a KF/Mg-Al-LDO/MCM-41 catalyst according to the mass ratio of the catalyst to the barbadosnut oil of 4 wt%, controlling the reaction temperature to be 65 ℃ and the reaction time to be 3 hours, carrying out rotary evaporation on the mixture under the conditions that the pressure is 0.03MPa, the temperature is 55 ℃ and the rotating speed is controlled to be 35r/min after the reaction is finished to remove unreacted methanol, adding deionized water to wash the mixture to be neutral, standing the mixture to be divided into a crude biodiesel layer, a glycerol layer and catalyst precipitate, taking the upper crude biodiesel layer to be placed in a separating funnel, dehydrating the mixture by using 25% anhydrous sodium sulfate, standing the mixture for centrifugation, and removing the precipitate to obtain the biodiesel.
Wherein the acid reduction treatment of raw material jatropha curcas oil: weighing a certain amount of barbadosnut seed oil, placing in a separating funnel, adding methanol according to the ratio of the barbadosnut seed oil to the methanol (g/mL) of 1:3, sufficiently shaking for 2min, standing for layering, removing the methanol on the upper layer, and measuring the acid value of the oil layer on the lower layer. Repeating the acid reduction operation until the acid value of the barbadosnut seed oil is less than 1mg KOH/g.
The biodiesel solid base catalyst KF/Mg-Al-LDO/MCM-41 prepared by the invention has the characteristics of stable structure, more alkaline sites, large comparative area and the like, and the single composite metal oxide solid base catalyst has the characteristics of collapse of interlayer structure, aggregation and agglomeration after high-temperature calcination, reduced catalytic activity area and reduced transesterification reaction efficiency. Due to the good dispersibility of the divalent and trivalent metal salts and the MCM-41 mesoporous silicon molecular sieve, the LDO/MCM-41 obtained by a coprecipitation method and high-temperature calcination has the advantages of large specific surface area, good adjustability, high dispersibility and strong acid and water resistance. KF is loaded by an isometric impregnation method, a new phase is formed after high-temperature calcination, and compared with a single composite metal oxide, the composite metal oxide has stronger alkalinity and more alkaline sites, so that the yield of the biodiesel is further improved.
The ATP is rich in surface charge, high in activity and good in dispersity, and can induce metal salt to precipitate, so that the MCM-41 molecular sieve prepared by taking the ATP as a silicon source can form high-dispersity LDH/MCM-41 with hydrotalcite, and after high-temperature calcination, the effective active area and alkali strength of the catalyst are increased, and the ester exchange efficiency is improved.
The design principle of the invention is that ATP is used as a silicon source, a template agent is added under an alkaline condition for hydrothermal crystallization, suction filtration, drying and high-temperature forging to generate an ordered hexagonal mesoporous structure MCM-41 mesoporous silicon molecular sieve with high controllability, high dispersibility and high specific surface area, a composite metal oxide with strong basicity is introduced through a coprecipitation method, finally KF is loaded through an isometric impregnation method, a new phase is formed after high-temperature calcination, alkaline sites are further increased, and the improvement of the ester exchange reaction yield is realized.
At present, raw oil for preparing biodiesel mainly comprises vegetable oil, such as soybean oil, olive oil and the like, but grain crops are not practical to be used as raw oil based on social factors such as large population, insufficient cultivated land and the like, so that the development of non-grain crops gradually becomes a development direction of large-scale preparation of biodiesel. The raw oil used in the invention is the barbadosnut oil, and the barbadosnut oil has the advantages of short growth period, high growth speed, high oil yield and low cost, has ideal physical and chemical properties and good compatibility with petroleum diesel, so the raw oil is an ideal raw oil for preparing the biodiesel. However, the content of free fatty acid in the roughly squeezed jatropha curcas seed oil is high, and the high content of free fatty acid can cause saponification reaction, thereby causing the yield reduction of biodiesel, and being not beneficial to the separation and purification of reaction products, so the raw oil of the jatropha curcas seed oil needs to be pretreated to reduce the content of free fatty acid. The barbadosnut seed oil treated by deacidification has low content of free fatty acid, is green and environment-friendly, and is ideal raw oil for preparing biodiesel.
The invention takes the prepared KF/Mg-Al-LDO/MCM-41 as a catalyst and the pretreated barbadosnut oil as raw oil to investigate the reusability of the catalyst. The research shows that the catalyst still has higher catalytic activity after being repeatedly used for 7 times. Based on rich ATP reserves, low cost and excellent physical and chemical properties of the catalyst, the catalyst is a novel biodiesel catalyst which is worthy of popularization.
Has the advantages that: compared with the prior art, the preparation method of KF/Mg-Al-LDO/MCM-41 and the application of biodiesel preparation have the following advantages:
the KF/Mg-Al-LDO/MCM-41 solid base catalyst prepared by the invention is high in SiO after being treated by acid2The MCM-41 molecular sieve prepared from ATP in percentage content has the advantages of large specific surface area, low cost, mild preparation conditions, good dispersibility and the like, composite metal oxide and KF are introduced by a coprecipitation method and an isometric impregnation method, a new phase is formed after high-temperature forging, and the MCM-41 molecular sieve is a solid base catalyst with good stability, alkaline sites and strong water resistance and acid resistance.
The invention has the following specific advantages:
1. ATP with high dispersibility and low cost is used as a silicon source, and compared with the traditional molecular sieve catalyst, the ATP has higher specific surface area and lower cost;
2. the alkaline sites are further improved by introducing the composite metal oxide and KF through a coprecipitation method and an isovolumetric impregnation method, so that the biodiesel has higher biodiesel transesterification yield;
3. after the traditional hydrotalcite (the divalent metal salt and the trivalent metal salt in the invention) is calcined at high temperature, a certain proportion of collapse agglomeration is caused between laminates, thereby reducing the exposure degree of the alkaline active sites. According to the invention, by introducing the MCM-41 mesoporous silicon molecular sieve, a more stable structure is formed with hydrotalcite after high-temperature roasting, and the loss of alkaline active sites is effectively overcome;
4. the invention takes the prepared KF/Mg-Al-LDO/MCM-41 as a catalyst and the pretreated barbadosnut seed oil as raw oil, can efficiently catalyze and form biodiesel, and still has higher catalytic activity after repeated times. And after the deacidification treatment, the saponification reaction is effectively inhibited, the physicochemical property is good, and the obtained product meets the use standard of the biodiesel.
Drawings
FIG. 1 is an SEM spectrogram of a KF/Mg-Al-LDO/MCM-41 catalyst;
FIG. 2 is a schematic diagram of the research on the reusability of KF/Mg-Al-LDO/MCM-41 catalyst.
Detailed description of the invention
The invention is further illustrated by the following examples in conjunction with the drawings.
Materials, reagents and the like used in the following examples are commercially available unless otherwise specified. The experimental procedures in the examples, which do not specify specific conditions, are generally carried out under conventional conditions or conditions recommended by the manufacturer.
Wherein ATP is purchased from national attapulgite Limited, Ming light, or other commercially available attapulgite clays.
The specific surface area, pore channel, pore diameter and pore volume in the present invention are defined as follows.
Specific surface area: the sum of the internal and external surface areas of the catalyst per unit mass is called the specific surface area of the catalyst.
Pore canal: the catalyst pellet has microporous channel.
Pore diameter: refers to the shape and size of the channels in the porous solid. The pores are rather highly irregular, usually viewed as circles and the size of the pores is expressed in terms of their radius.
Pore volume: the sum of all pore volumes within the catalyst.
Example 1
(1) Weighing 10g of ATP, mixing and dispersing in 100mL of HCl solution with the concentration of 2mol/L, soaking at 80 ℃ for 24h, filtering, placing filter residue at 100 ℃ and drying for 3h to obtain acid modified ATP;
(2) weighing 3g of acid-modified ATP in the step (1), adding the acid-modified ATP into 20mL of 0.4mol/L NaOH solution, adding 20mL of 10% CTAB solution under the condition of magnetic stirring, adjusting the pH value to 10-11 by using 1moI/L hydrochloric acid solution, stirring for 1h, then transferring to a reaction kettle, crystallizing for 72h at the temperature of 110 ℃, repeatedly washing the obtained product with deionized water, drying for 3h at the temperature of 80 ℃, and then roasting for 3h at the high temperature of 500 ℃ to remove a template agent, thus obtaining the MCM-41 mesoporous silicon molecular sieve;
(3) 6.0990g of MgCl were weighed2·6H2O and 2.4143g of AlCl3·6H2Adding ultrapure water into the O, stirring to prepare a uniformly dispersed salt solution A, weighing 4.2567g of MCM-41 prepared in the step (2), adding the weighed solution into the ultrapure water, stirring to form a dispersed solution B, and mixing the solution A and the solution B for 200W and carrying out ultrasonic treatment for 40 min. Stirring and slowly dripping 0.8mol/L ammonia water solution until the solution is colloidal, and keeping the pH value between 10 and 11 in the dripping process. Crystallizing at 80 deg.C for 18 hr after dripping, filtering, drying at 80 deg.C for 3 hr to obtain white precipitate, and calcining at 600 deg.C for 4 hr to obtain Mg3-Al1-LDO2/MCM-411；
(4) Weighing 3g of Mg-Al-LDO/MCM-41, adding into 3.9mL of 15 wt% KF solution, soaking for 16h at 30 ℃, drying for 3h at 80 ℃, and roasting for 3h at 600 ℃ to obtain the catalyst KF/Mg3-Al1-LDO2/MCM-411And is denoted as S1.
Mg prepared in this example3-Al1-LDO2/MCM-411The SEM spectrogram is shown in figure 1, and figure 1 illustrates that the surface of the catalyst after KF and LDO loading has a plurality of spherical and worm-shaped small particles, which proves that the active ingredients and the catalyst have interaction and the alkaline sites are improved.
The specific method for preparing the biodiesel by the KF/Mg-Al-LDO/MCM-41 catalyst comprises the following steps:
acid reduction treatment of raw oil: weighing 30g of barbadosnut seed oil, placing the barbadosnut seed oil in a separating funnel, adding 90mL of methanol, fully shaking for 2min, standing for layering, removing the methanol on the upper layer, and measuring the acid value of the oil layer on the lower layer. Repeating the acid reduction operation until the acid value of the barbadosnut seed oil is less than 1mg KOH/g.
Ester exchange reaction: weighing 20g of the barbadosnut seed oil subjected to acid reduction treatment, placing the barbadosnut seed oil in a round-bottom flask, controlling the molar ratio of methanol to barbadosnut seed oil to be 10:1, and adding 4 wt% of catalyst KF/Mg into the barbadosnut seed oil according to the mass of the barbadosnut seed oil3-Al1-LDO2/MCM-411The catalyst is used, the reaction temperature is 65 ℃, and the reaction time is 3 hours.
Separation and purification: after the reaction is finished, the mixture is subjected to rotary evaporation under the conditions that the pressure is 0.03MPa, the temperature is 55 ℃ and the rotating speed is controlled at 35r/min to remove the unreacted methanol. Adding deionized water for washing, standing, separating into a crude biodiesel layer, a glycerin layer and a catalyst precipitate, placing the upper crude biodiesel layer in a separating funnel, dehydrating with 25% anhydrous sodium sulfate, standing, centrifuging, and removing the precipitate to obtain the biodiesel.
Example 2
Example 2 catalyst preparation the MgCl of step (3) was adjusted as in example 12·6H2AlCl of O and3·6H2the mass of O is 10.1650g and 2.4143g respectively, and the prepared catalyst is KF/Mg5-Al1-LDO2/MCM-411Is denoted as S2。
Example 2 catalyst S2The preparation method of biodiesel of (2) is the same as in example 1.
Example 3
Example 3 catalyst preparation same as example 1, adjusting m (MCM-41): m (LDH) of step (3) to 1:1, weighing 8.5133g of MCM-41 molecular sieve, and KF/Mg as the catalyst obtained3-Al1-LDO1/MCM-411Is marked as S3
Example 3 catalyst S3The biodiesel preparation method of (2) was the same as in example 1.
Example 4
Example 4 was prepared identically to example 1, except that: in the step (1), the concentration of HCl solution is 1mol/L, the solid-to-liquid ratio of ATP to HCl solution is 1:5g/mL, the mixture is soaked for 20 hours at 80 ℃, and filter residue is dried for 2 hours at 100 ℃ after suction filtration; in the step (2), the concentration of NaOH solution is 0.2mol/L, the concentration of CTAB solution is 5%, the solid-to-liquid ratio of acid modified ATP to NaOH solution is 1:5g/mL, hydrothermal crystallization is carried out for 96h at the temperature of 90 ℃, and the obtained product is washed with water, dried and then roasted at the high temperature of 400 ℃ for 5h to remove template agent CTAB; MgCl in step (3)2·6H2O and AlCl3·6H2O in a molar ratio n (Mg)2+):n(Al3+) Is 1: 1; MC (monomer casting)The mass M (LDH) of M-41 and divalent metal salt and trivalent metal salt is 1: 1; performing ultrasonic treatment for 30min under the condition of power of 300W and frequency of 50Hz in the step (3), dropwise adding an ammonia water solution with the concentration of 0.5mol/L until the solution is colloidal, standing and aging the mixed sol at 60 ℃ for 18h, filtering and drying the white precipitate, and roasting the white precipitate in a muffle furnace at 400 ℃ for 6 h; in the step (4), the KF solution accounts for 10 wt%, and the ratio of the catalyst LDO/MCM-41 to the KF solution in the equal-volume impregnation method is 1:1.5 g/mL; the dipping temperature is 40 ℃, the dipping time is 12h, and the dried product is roasted for 6h at 400 ℃.
Example 5
Example 5 was prepared identically to example 1, except that: in the step (1), the concentration of the HCl solution is 3mol/L, and the solid-to-liquid ratio of ATP to the HCl solution is 1:15 g/mL; in the step (2), the concentration of NaOH solution is 0.6mol/L, the concentration of CTAB solution is 15%, the solid-to-liquid ratio of acid modified ATP to NaOH solution is 1:10g/mL, hydrothermal crystallization is carried out for 48h at the temperature of 120 ℃, and the obtained product is washed with water, dried and then roasted at the high temperature of 800 ℃ for 2h to remove the template agent CTAB; MgCl in step (3)2·6H2O and AlCl3·6H2O in a molar ratio n (Mg)2+):n(Al3+) Is 5: 1; the mass m (LDH) of the MCM-41 and the divalent metal salt and the trivalent metal salt is 3: 1; performing ultrasonic treatment for 60min under the condition of power of 300W and frequency of 50Hz in the step (3), dropwise adding 1mol/L ammonia water solution until the solution is colloidal, standing and aging the mixed sol at 90 ℃ for 6h, filtering and drying, and roasting the white precipitate in a muffle furnace at 800 ℃ for 3 h; in the step (4), the KF solution accounts for 30 wt%, the dipping temperature is 30 ℃, the dipping time is 12 hours, and the KF solution is roasted for 3 hours at 800 ℃ after drying.
Comparative example 1
Weighing 20g of ATP, mixing and dispersing in 200mL of HCl solution with the concentration of 2mol/L, soaking at 60 ℃ for 12h, repeatedly washing with deionized water after suction filtration until the filtrate is neutral, drying the filter residue at 100 ℃ for 3h, and grinding for later use, wherein the mark D is1。
Comparative example 2
3g of comparative example 1, D1Adding acid modified ATP into 20mL NaOH solution with concentration of 0.4mol/L, adding 10% CTAB solution 20mL under magnetic stirring, adjusting pH to 10-11 with hydrochloric acid solution 1moI/L, stirring for 1h, transferring into a reaction kettle, crystallizing at 110 deg.CAnd (3) 72h, repeatedly washing the obtained product with deionized water, drying at 80 ℃ for 3h, then placing at 500 ℃ for high-temperature roasting for 3h to remove the template agent, and obtaining the MCM-41 mesoporous silicon molecular sieve marked as D2。
Comparative example 3
Taking n (Mg)2+):n(Al3+) 6.0990g of MgCl were weighed for 3:12·6H2O and 2.4143g of AlCl3·6H2Adding pure water into the O, stirring to prepare a uniformly dispersed salt solution, slowly dropwise adding 30% (mL/mL) ammonia water, and adjusting the pH value to 10-11 by using 1moI/L hydrochloric acid solution. Standing at 100 deg.C for crystallization for 24h, vacuum filtering, drying at 80 deg.C for 3h, and calcining at 500 deg.C for 6h to obtain Mg3-Al1LDO, denoted D3。
Comparative example 3 catalyst D3The biodiesel preparation method of (2) was the same as in example 1.
Comparative example 4
Taking n (Ca)2+):n(Al3+) 6.5724g of CaCl were weighed at a ratio of 3:12·6H2O and 2.4143g of AlCl3·6H2Adding pure water into the O, stirring to prepare a uniformly dispersed salt solution, slowly dropwise adding 30% (mL/mL) ammonia water, and adjusting the pH value to 10-11 by using 1moI/L hydrochloric acid solution. Standing at 100 deg.C for crystallization for 24h, vacuum filtering, drying at 80 deg.C for 3h, and calcining at 500 deg.C for 6h to obtain Ca3-Al1LDO, denoted D4。
Comparative example 4 catalyst D4The biodiesel preparation method of (2) was the same as in example 1.
Comparative example 5
(1) Weighing 10g of ATP, mixing and dispersing in 100mL of HCl solution with the concentration of 2mol/L, soaking at 80 ℃ for 24h, repeatedly washing with deionized water after suction filtration until the filtrate is neutral, and drying the filter residue at 100 ℃ for 3 h;
(2) weighing 3g of acid modified ATP in the step (1), adding the acid modified ATP into 20mL of 0.4mol/L NaOH solution, adding 20mL of 10% CTAB solution under the condition of magnetic stirring, adjusting the pH value to 10-11 by using 1moI/L hydrochloric acid solution, transferring the obtained product into a reaction kettle, crystallizing for 72 hours at the temperature of 110 ℃, repeatedly washing the obtained product with deionized water, drying for 3 hours at the temperature of 80 ℃, and then roasting for 3 hours at the high temperature of 500 ℃ to remove a template agent, thus obtaining the MCM-41 mesoporous silicon molecular sieve;
(3) 6.0990g of Mg (Cl) were weighed out2·6H2O and 2.4143g of AlCl3·6H2Adding ultrapure water into the O, stirring to prepare a uniformly dispersed salt solution A, weighing 4.2567g of MCM-41 prepared in the step (2), adding the MCM-41 into the ultrapure water, stirring to form a dispersed solution B, and then carrying out ultrasonic mixing on the solution A and the solution B for 40 min. Stirring and slowly dripping 0.8mol/L NaOH solution, and keeping the pH value between 10 and 11 in the dripping process. Crystallizing at 80 deg.C for 18 hr after dripping, filtering, drying at 80 deg.C for 3 hr to obtain white precipitate, and calcining at 600 deg.C for 4 hr to obtain Mg3-Al1-LDO2/MCM-411Is marked as D5。
Comparative example 5 catalyst D5The biodiesel preparation method of (2) was the same as in example 1.
BET characterization of the catalysts prepared in examples 1-3 and comparative examples 1-5 above and GC analysis of the biodiesel prepared from the catalysts were performed, and the results are shown in Table 1.
TABLE 1 analysis of catalyst physical Properties and biodiesel production yield
As can be seen from Table 1, in comparative examples 1-2, D2The specific surface area, the pore volume and the pore diameter of the porous material are all larger than D1The reason is that the catalyst property is greatly improved after the crude ATP is separated, purified and acid modified, and the SiO is2The content is greatly improved, so that when the catalyst is used as a silicon source to prepare the MCM-41 molecular sieve, the catalyst carrier with good dispersion performance, large specific surface area and ordered structure can be obtained.
In comparative examples 3 to 4, catalyst D3The specific surface area and the pore diameter of the porous material are slightly larger than D4Therefore, theoretically, the catalytic activity of the catalyst Ca-Al-LDO should be higher than that of Mg-Al-LDO, but the actual catalytic efficiency of biodiesel is slightly lower than that of D4This is because the water and acid resistance of the catalyst Mg-Al-LDO is stronger than that of the catalyst Ca-Al-LDO. Therefore, magnesium-aluminum hydrotalcite is more suitable than calcium-aluminum hydrotalcite for raw oil having a high acid value.
In comparative examples 3 and 5, MCM-41 mesoporous silica molecular sieve is subjected to coprecipitation, loading of magnesium and aluminum, and water-slipping to obtain D5The specific surface area is reduced, which shows that the magnesium-aluminum hydrotalcite is successfully compounded on the surface of the molecular sieve, so that the solid base catalyst has a certain degree of water resistance and acid resistance, and the prepared catalyst has strong dispersibility and can be uniformly dispersed in an oil phase and an organic phase, thereby showing good performance in catalyzing the biodiesel ester exchange reaction.
In examples 1 to 3 and comparative example 5, S2Has a specific surface area, a pore diameter and a pore volume lower than S2This may be due to S2The molar ratio of the magnesium-aluminum hydrotalcite is higher than S1The molecular sieve is stacked on the surface of the molecular sieve, so that the channel is blocked, and the yield of the biodiesel is reduced; s3Relative to S1The mass ratio of the hydrotalcite to the molecular sieve is reduced, the hydrotalcite is not fully coated on the surface of the molecular sieve through the specific surface area, and the suitable m (LDH) to m (MCM-41) ratio is 2: 1; s1Relative to D5By adopting an isometric impregnation method to load KF, the conversion rate of biodiesel is improved, because a large amount of alkaline sites are introduced, a new phase is formed after high-temperature calcination, and the reaction rate of ester exchange reaction is accelerated.
In addition, for the catalyst S in example 11And (4) carrying out alkali strength measurement, alkali quantity distribution measurement and catalyst repeatability test.
The determination of the alkali strength was carried out using the Hammett indicator method, and the catalyst alkali strength was determined by comparing the color changes of four Hammett indicators, bromothymol blue (pKa ═ 7.2), phenolphthalein (pKa ═ 9.8), 2, 4-dinitroaniline (pKa ═ 15), and p-nitroaniline (pKa ═ 18.4). The specific operation is as follows: 1g of the activated catalyst was weighed, and then 20mL of distilled n-hexane and a few drops of Hammett's indicator were added to the test tube and sufficiently shaken for 30 min. And waiting for a period of time, and observing the color change of the mixed solution. Catalyst S1The alkali strength is measured to be 15-18And 4, belonging to strong alkali in solid.
The total alkali amount of the prepared solid base catalyst was determined by consumption of benzoic acid and change in coloration of the indicator using benzoic acid-indicator titration. The specific operation is as follows: weighing a certain amount of solid base catalyst, adding 10mL of n-hexane, titrating with 0.01mol/L benzoic acid-ethanol solution, shaking uniformly, and repeating the operations until the color of the indicator disappears. Catalyst S1The KF loading is 15%, and the total alkali amount can reach 16.28 mmol/g.
For catalyst S prepared in example 11The recycling performance is inspected, and the specific operations are as follows: washing the used catalyst with methanol and petroleum ether for 3 times, removing grease reactant attached to the surface of the catalyst, drying at 100 ℃ for 6h after washing, and putting the washed catalyst into the next biodiesel preparation reaction. Under the same reaction conditions (same transesterification conditions as in example 1), the catalyst was reused 7 times and the biodiesel yield was recorded separately. As can be seen from FIG. 2, catalyst S1With the increase of the repeated use times, the yield of the biodiesel shows a weak descending trend, and S1The conversion rate of the biodiesel is 97.52% when the biodiesel is used for the first time, the conversion rate of the biodiesel still reaches 90.61% after the biodiesel is repeatedly used for 7 times, the biodiesel shows good reusability, the catalytic activity is higher, and the jatropha curcas seed oil still contains certain water and acidity after being treated, so that the water resistance and acid resistance of the biodiesel can be basically shown to be poor when the yield is greatly reduced.
Claims (1)
1. An application of solid alkali catalyst KF/Mg-Al-LDO/MCM-41 in the preparation process of biodiesel, the preparation process comprises the steps of taking the barbadosnut oil treated by reducing acid, controlling the molar ratio of methanol to the barbadosnut oil to be 10:1, adding a KF/Mg-Al-LDO/MCM-41 catalyst according to the mass ratio of the catalyst to the barbadosnut seed oil of 4 wt%, reacting at 65 ℃ for 3h, carrying out rotary evaporation on the mixture under the conditions that the pressure is 0.03MPa, the temperature is 55 ℃ and the rotating speed is controlled at 35r/min after the reaction is finished to remove unreacted methanol, adding deionized water to wash the mixture to be neutral, standing the mixture to obtain a crude biodiesel layer, placing the crude biodiesel layer on a separating funnel, dehydrating the crude biodiesel layer by using 25% anhydrous sodium sulfate, standing and centrifuging the mixture, and removing the precipitate to obtain the biodiesel;
the preparation method of the solid base catalyst KF/Mg-Al-LDO/MCM-41 is characterized by comprising the following steps:
(1) mixing and dispersing ATP in HCl solution, soaking, filtering, and drying filter residue to obtain acid modified ATP;
(2) adding acid modified ATP into NaOH solution, adding CTAB solution under stirring, carrying out hydrothermal crystallization after stirring, washing and drying the obtained product, and calcining at high temperature to obtain the MCM-41 mesoporous silicon molecular sieve;
(3) adding a divalent metal salt and a trivalent metal salt into ultrapure water, stirring to prepare a uniformly dispersed salt solution A, adding the MCM-41 mesoporous silica molecular sieve prepared in the step (2) into the ultrapure water, stirring to form a dispersed solution B, ultrasonically mixing the solution A and the solution B, stirring, slowly dropwise adding an ammonia water solution, standing and aging the mixed sol after dropwise adding is finished, filtering, drying to obtain a white precipitate, and calcining the white precipitate at high temperature to obtain LDO/MCM-41; the mass of the MCM-41, the divalent metal salt and the trivalent metal salt in the step (3) is expressed by m (MCM-41) and m (LDH), and m (MCM-41) is 2: 1;
(4) adding the LDO/MCM-41 into a KF solution by an isometric impregnation method, drying and roasting at high temperature after impregnation to obtain a biodiesel catalyst KF/LDO/MCM-41;
in the step (1), the concentration of the HCl solution is 1-3mol/L, the solid-to-liquid ratio of ATP to the HCl solution is 1:5-15g/mL, the mixture is soaked for 20-24h at 80 ℃, and after suction filtration, filter residues are dried for 2-3h at 100 ℃; in the step (2), the concentration of the NaOH solution is 0.2-0.6mol/L, the concentration of the CTAB solution is 5-15% g/mL, and the solid-to-liquid ratio of the acid modified ATP to the NaOH solution is 1:5-10 g/mL; in the step (2), the hydrothermal crystallization is performed for crystallization for 48 to 96 hours at the temperature of between 90 and 120 ℃, and the crystallization is performed for 2 to 5 hours at the high temperature of between 400 and 800 ℃ after being washed and dried to remove the template agent CTAB; the divalent metal salt in the step (3) is MgCl2·6H2O, trivalent metal salt is AlCl3·6H2O, wherein the divalent metal salt is in contact with the trivalent metalThe metal salt is used in a molar ratio n (Mg)2+)、n(Al3+) Is represented by n (Mg)2+):n(Al3+) 1-5: 1; performing ultrasonic treatment for 30-60min under the condition of power of 200-300W and frequency of 50Hz in the step (3), dropwise adding 0.5-1mol/L ammonia water solution until the solution is colloidal, keeping the pH value of 10-11 in the dropwise adding process, standing and aging the mixed sol at 60-90 ℃ for 6-18h, filtering and drying the white precipitate, and roasting the white precipitate in a muffle furnace at 400-800 ℃ for 3-6 h; the KF solution in the step (4) is 10-30 wt%, and the ratio of the catalyst LDO/MCM-41 to the KF solution in the equal-volume impregnation method is 1:1.3-1.5 g/mL; in the step (4), the dipping temperature is 30-40 ℃, the dipping time is 12-24h, and the dried product is roasted at 400-800 ℃ for 3-6 h.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011319446.2A CN112264085B (en) | 2020-11-23 | 2020-11-23 | Solid base catalyst KF/Mg-Al-LDO/MCM-41 and preparation method and application thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011319446.2A CN112264085B (en) | 2020-11-23 | 2020-11-23 | Solid base catalyst KF/Mg-Al-LDO/MCM-41 and preparation method and application thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112264085A CN112264085A (en) | 2021-01-26 |
| CN112264085B true CN112264085B (en) | 2022-06-14 |
Family
ID=74340498
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011319446.2A Active CN112264085B (en) | 2020-11-23 | 2020-11-23 | Solid base catalyst KF/Mg-Al-LDO/MCM-41 and preparation method and application thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112264085B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113856741B (en) * | 2021-11-19 | 2023-06-20 | 陕西科技大学 | Hydrotalcite solid base, preparation method thereof and application of hydrotalcite solid base in efficient catalysis of cyclopentanone trimerization |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101249452A (en) * | 2008-03-19 | 2008-08-27 | 北京化工大学 | Load type solid body base catalyst of synthesizing dimethyl carbonate and method of preparing the same |
| CN106145132A (en) * | 2016-06-28 | 2016-11-23 | 常州大学 | A kind of method utilizing attapulgite to prepare ordered mesoporous material Al MCM 41 |
| CN107541234A (en) * | 2017-09-02 | 2018-01-05 | 湘潭大学 | A kind of method of the immobilized potassium fluoride catalyzed by solid base biodiesel synthesis of houghite |
| CN111054425A (en) * | 2019-11-21 | 2020-04-24 | 陕西科技大学 | hydrotalcite/MCM-41 mesoporous silicon composite solid base catalyst and in-situ preparation method and application thereof |
| CN111468149A (en) * | 2020-05-15 | 2020-07-31 | 淮阴工学院 | Novel biodiesel solid catalyst KF/Ca-Mg-Al-O and preparation method and application thereof |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5964327B2 (en) * | 2011-02-14 | 2016-08-03 | カウンスィル オブ サイエンティフィック アンド インダストリアル リサーチＣｏｕｎｃｉｌ Ｏｆ Ｓｃｉｅｎｔｉｆｉｃ ＆ Ｉｎｄｕｓｔｒｉａｌ Ｒｅｓｅａｒｃｈ | Improved process for producing fatty acid alkyl esters (biodiesel) from triglyceride oils by using environmentally friendly solid base catalysts |
-
2020
- 2020-11-23 CN CN202011319446.2A patent/CN112264085B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101249452A (en) * | 2008-03-19 | 2008-08-27 | 北京化工大学 | Load type solid body base catalyst of synthesizing dimethyl carbonate and method of preparing the same |
| CN106145132A (en) * | 2016-06-28 | 2016-11-23 | 常州大学 | A kind of method utilizing attapulgite to prepare ordered mesoporous material Al MCM 41 |
| CN107541234A (en) * | 2017-09-02 | 2018-01-05 | 湘潭大学 | A kind of method of the immobilized potassium fluoride catalyzed by solid base biodiesel synthesis of houghite |
| CN111054425A (en) * | 2019-11-21 | 2020-04-24 | 陕西科技大学 | hydrotalcite/MCM-41 mesoporous silicon composite solid base catalyst and in-situ preparation method and application thereof |
| CN111468149A (en) * | 2020-05-15 | 2020-07-31 | 淮阴工学院 | Novel biodiesel solid catalyst KF/Ca-Mg-Al-O and preparation method and application thereof |
Non-Patent Citations (1)
| Title |
|---|
| Biodiesel production from jatropha oil catalyzed by immobilized Burkholderia cepacia lipase on modified attapulgite;Qinghong You等;《Bioresource Technology》;20130902;第148卷;全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112264085A (en) | 2021-01-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Li et al. | Efficient heterogeneous acid synthesis and stability enhancement of UiO-66 impregnated with ammonium sulfate for biodiesel production | |
| Sharma et al. | Latest developments on application of heterogenous basic catalysts for an efficient and eco friendly synthesis of biodiesel: A review | |
| CN101492603B (en) | Method for producing biodiesel by using tallowseed oil and special solid catalyst thereof | |
| US5064628A (en) | Novel ceric oxides and preparation thereof | |
| Zhang et al. | Magnetically recyclable basic polymeric ionic liquids for efficient transesterification of Firmiana platanifolia Lf oil into biodiesel | |
| CN110124729B (en) | Coated catalyst for slurry bed Fischer-Tropsch synthesis and preparation method thereof | |
| CN102826608A (en) | Method for preparing bismuth ferrite powder by solvothermal method | |
| CN109847759B (en) | Cobalt-cerium/sepiolite catalyst and preparation method and application thereof | |
| CN111468149B (en) | Biodiesel solid catalyst KF/Ca-Mg-Al-O and preparation method and application thereof | |
| CN109876790A (en) | A kind of CaO-MgO-Al2O3The method of catalyzed by solid base biodiesel synthesis | |
| CN108531295B (en) | Method for catalytically synthesizing biodiesel by KF/MgFeLaO solid base | |
| CN112264085B (en) | Solid base catalyst KF/Mg-Al-LDO/MCM-41 and preparation method and application thereof | |
| KR101337301B1 (en) | Aluminosilicate Nano-spheres having 3-Dimensional Open Pores, Method for Preparing the Same and Method for Producing Acrylic Acid from Glycerol Using the Same | |
| Fazaeli et al. | Production of biodiesel through transesterification of soybean oil using ZIF-8@ GO doped with sodium and potassium catalyst | |
| CN102071267A (en) | Method for coproducing xylose, white carbon black and active carbon from rice hulls | |
| CN106540674B (en) | A kind of metal-doped zirconia catalyst and preparation method thereof with catalyzing and synthesizing the application in gas catalyzed conversion | |
| CN102259004A (en) | Catalyst used in coal natural gas methanation reactor and preparation method thereof | |
| CN102259005B (en) | Catalyst for assisting coal natural gas methanation reactor and preparation method thereof | |
| CN110787804A (en) | Hydrodeoxygenation sulfur-free nickel-based Ni/Al2O3-ZrO2Catalyst and process for preparing same | |
| CN111286408A (en) | Method for preparing biodiesel by catalyzing jatropha curcas oil through zirconium-based MOFs material loaded with ionic liquid | |
| CN110935478B (en) | Preparation method of methanol synthesis catalyst | |
| CN110935456B (en) | Preparation method of catalyst for synthesizing methanol | |
| CN111841555B (en) | Direct cracking of methanol to produce CO and H 2 Catalyst, preparation method and application | |
| CN111686740A (en) | Preparation method of methanol synthesis catalyst | |
| CN106732678A (en) | A kind of carbon-based magnetic solid acid catalyst and its application in biodiesel preparation |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| EE01 | Entry into force of recordation of patent licensing contract | ||
| EE01 | Entry into force of recordation of patent licensing contract |
Application publication date: 20210126 Assignee: NANJING ALLY CHEMICAL S&T Co.,Ltd. Assignor: HUAIYIN INSTITUTE OF TECHNOLOGY Contract record no.: X2022980020829 Denomination of invention: A Solid Alkali Catalyst KF/Mg Al LDO/MCM-41 and Its Preparation and Application Granted publication date: 20220614 License type: Common License Record date: 20221111 |