EP0404867A1 - Magnesium oxide in fine powder form and its use - Google Patents
Magnesium oxide in fine powder form and its useInfo
- Publication number
- EP0404867A1 EP0404867A1 EP89909119A EP89909119A EP0404867A1 EP 0404867 A1 EP0404867 A1 EP 0404867A1 EP 89909119 A EP89909119 A EP 89909119A EP 89909119 A EP89909119 A EP 89909119A EP 0404867 A1 EP0404867 A1 EP 0404867A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- magnesium oxide
- oxide according
- substance
- particles
- fine powder
- 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.)
- Pending
Links
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 title claims abstract description 35
- 239000000395 magnesium oxide Substances 0.000 title claims abstract description 32
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 title claims abstract description 27
- 239000000843 powder Substances 0.000 title claims abstract description 15
- 239000002245 particle Substances 0.000 claims abstract description 17
- 239000000126 substance Substances 0.000 claims abstract description 12
- 239000011164 primary particle Substances 0.000 claims abstract description 9
- 239000000919 ceramic Substances 0.000 claims abstract description 6
- 230000002209 hydrophobic effect Effects 0.000 claims abstract 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 6
- TWRXJAOTZQYOKJ-UHFFFAOYSA-L Magnesium chloride Chemical compound [Mg+2].[Cl-].[Cl-] TWRXJAOTZQYOKJ-UHFFFAOYSA-L 0.000 claims description 6
- 239000011248 coating agent Substances 0.000 claims description 4
- 238000000576 coating method Methods 0.000 claims description 4
- 229910001629 magnesium chloride Inorganic materials 0.000 claims description 3
- 229910052751 metal Inorganic materials 0.000 claims description 3
- 239000002184 metal Substances 0.000 claims description 3
- 229910052757 nitrogen Inorganic materials 0.000 claims description 3
- 239000000344 soap Substances 0.000 claims description 3
- 238000001179 sorption measurement Methods 0.000 claims description 3
- 238000004519 manufacturing process Methods 0.000 claims description 2
- 229920000620 organic polymer Polymers 0.000 claims description 2
- 125000002524 organometallic group Chemical group 0.000 claims description 2
- 229920001296 polysiloxane Polymers 0.000 claims description 2
- 235000003441 saturated fatty acids Nutrition 0.000 claims description 2
- 150000004671 saturated fatty acids Chemical class 0.000 claims description 2
- 150000004756 silanes Chemical class 0.000 claims description 2
- 235000021122 unsaturated fatty acids Nutrition 0.000 claims description 2
- 150000004670 unsaturated fatty acids Chemical class 0.000 claims description 2
- 239000004094 surface-active agent Substances 0.000 claims 1
- 238000004438 BET method Methods 0.000 abstract 1
- 239000000463 material Substances 0.000 description 4
- 230000036571 hydration Effects 0.000 description 3
- 238000006703 hydration reaction Methods 0.000 description 3
- 239000004575 stone Substances 0.000 description 3
- 239000011159 matrix material Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 1
- 239000013543 active substance Substances 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000005056 compaction Methods 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000011777 magnesium Substances 0.000 description 1
- 239000001095 magnesium carbonate Substances 0.000 description 1
- 235000014380 magnesium carbonate Nutrition 0.000 description 1
- ZLNQQNXFFQJAID-UHFFFAOYSA-L magnesium carbonate Chemical compound [Mg+2].[O-]C([O-])=O ZLNQQNXFFQJAID-UHFFFAOYSA-L 0.000 description 1
- 229910000021 magnesium carbonate Inorganic materials 0.000 description 1
- 239000012798 spherical particle Substances 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- 238000005979 thermal decomposition reaction Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 230000004584 weight gain Effects 0.000 description 1
- 235000019786 weight gain Nutrition 0.000 description 1
Classifications
-
- 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
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
- C04B35/03—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on magnesium oxide, calcium oxide or oxide mixtures derived from dolomite
- C04B35/04—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on magnesium oxide, calcium oxide or oxide mixtures derived from dolomite based on magnesium oxide
- C04B35/053—Fine ceramics
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
- C01F5/00—Compounds of magnesium
- C01F5/02—Magnesia
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
- C01F5/00—Compounds of magnesium
- C01F5/02—Magnesia
- C01F5/06—Magnesia by thermal decomposition of magnesium compounds
- C01F5/10—Magnesia by thermal decomposition of magnesium compounds by thermal decomposition of magnesium chloride with water vapour
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
- C01P2004/61—Micrometer sized, i.e. from 1-100 micrometer
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
- C01P2004/62—Submicrometer sized, i.e. from 0.1-1 micrometer
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/12—Surface area
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/14—Pore volume
Definitions
- the invention relates to a magnesium oxide with a
- MgO content 95% by weight, preferably> 98% by weight, in the form of a fine powder with a particle size ⁇ 15 ⁇ m and a specific surface area ⁇ 20 m 2 / g, determined according to BET from the nitrogen adsorption isotherm.
- a material that is particularly suitable for fire resistance is a micropowder based on high-purity magnesium oxide.
- micropowder that can be used to fill the cavities in a ceramic matrix and to produce high density
- Ceramics are suitable, but are not limited to these applications.
- such a magnesium oxide micropowder is characterized in that it has a statistical mean value of the grain shape factor of the primary particles between 1 and 1.5 and the particles have a coating of a hydrophobizing substance.
- the grain shape factor K is due to the relationship
- the grain shape factor K a dimensionless number, is 1 in the case of an exactly spherical particle and is larger the more the shape of the particle deviates from the spherical shape.
- the grain shape factor with a statistical mean of the distribution curve in the range between 1 and 1.5 therefore defines primary particles of approximately spherical shape.
- Suitable hydrophobing substances with which the magnesium oxide particles are coated or coated according to the invention are surface-active substances, in particular unsaturated or saturated fatty acids or their derivatives, organometallic substances - such as silanes, titanates, zircoaluminates, metal soaps - or silicones or organic polymers.
- the magnesium oxide according to the invention generally has a content of 0.1 to 10% by weight of hydrophobicizing substance.
- the micropowder according to the invention consists, in addition to isolated primary particles, only of relatively small agglomerates of primary particles.
- the powder has a particle size ⁇ 15 ⁇ m, preferably from 0.2 to 15 ⁇ m.
- the size of the primary particles is preferably in the range from 0.2 to 2 ⁇ m.
- the specific surface area of the micropowder which can be determined according to BET from the nitrogen adsorption isotherm, should not be too high; in the magnesium oxide according to the invention it is below 20 m / g, preferably in the range from 2 to 7 m 2 / g.
- a magnesium oxide powder which is particularly suitable for the purposes of the invention can be obtained by pyrohydrolysis of a magnesium chloride solution, it being possible to use a spray roasting furnace for the thermal decomposition. The powder obtained is then coated with the hydrophobicizing substance.
- a magnesium oxide powder A was obtained by spray-roasting a purified magnesium chloride solution. Part of this material was mixed with a metal soap for a long time (6 hours), and thereby the coated magnesium oxide powder B was obtained.
- the properties of these two materials A and B are compared in Table 1 below:
- the values d 30 rd so and d * 0 indicate those particle diameters in which 30, 50 and 70% of the material are smaller than the specified value.
- the degree of hydration was determined after the samples had been exposed in an environmental cabinet for 48 hours at a temperature of 40 ° C. in an atmosphere with 95% relative air humidity. The degree of hydration was determined from the weight gain due to the absorption of water, a degree of hydration of 100% corresponding to the complete conversion of the MgO to Mg (OH) 2 .
- Example 2
- Stone mixtures were produced from 10% by weight of untreated magnesium oxide powder A or 10% by weight of coated magnesium oxide powder B and in each case 90% by weight of sintered magnesia with a grain size of less than 3 mm, obtained from low-iron natural magnesite. The mixtures were pressed into stones and these were fired at a temperature of 1850 ° C. Table 2 shows the test values determined on the stones.
- Example 3 Shaped articles were produced from 100% by weight of magnesium oxide powder A or 100% by weight of magnesium oxide powder B and fired at a temperature of 1600 ° C. Table 3 shows the test results.
Abstract
Un oxyde de magnésium sous forme d'une poudre fine que l'on peut utiliser pour produire des céramiques de haute densité a une teneur en MgO supérieure à 95 % en poids, de préférence supérieure à 98 % en poids, des particules de dimensions inférieures à 15 mum, une superficie spécifique inférieure à 20 m2/g selon la méthode B.E.T. et une valeur statistique moyenne du facteur de forme granulométrique des particules primaires comprise entre 1 et 1,5. Les particules sont enrobées d'une substance hydrophobe tensio-active.A magnesium oxide in the form of a fine powder which can be used to produce high density ceramics has an MgO content of greater than 95% by weight, preferably greater than 98% by weight, smaller particle sizes at 15 mum, a specific surface area of less than 20 m2 / g according to the BET method and an average statistical value of the particle size form factor of the primary particles of between 1 and 1.5. The particles are coated with a surface-active hydrophobic substance.
Description
Claims
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AT2006/88A AT392464B (en) | 1988-08-10 | 1988-08-10 | MAGNESIUM OXIDE IN THE FORM OF A FINE POWDER AND ITS USE |
AT2006/88 | 1988-08-10 |
Publications (1)
Publication Number | Publication Date |
---|---|
EP0404867A1 true EP0404867A1 (en) | 1991-01-02 |
Family
ID=3525806
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP89909119A Pending EP0404867A1 (en) | 1988-08-10 | 1989-08-03 | Magnesium oxide in fine powder form and its use |
EP89890206A Expired - Lifetime EP0354896B1 (en) | 1988-08-10 | 1989-08-03 | Magnesium oxide micropowder and its use |
Family Applications After (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP89890206A Expired - Lifetime EP0354896B1 (en) | 1988-08-10 | 1989-08-03 | Magnesium oxide micropowder and its use |
Country Status (12)
Country | Link |
---|---|
US (1) | US5106608A (en) |
EP (2) | EP0404867A1 (en) |
JP (1) | JPH064487B2 (en) |
KR (1) | KR900701660A (en) |
AT (2) | AT392464B (en) |
AU (1) | AU619885B2 (en) |
BR (1) | BR8907050A (en) |
CA (1) | CA1334156C (en) |
DE (1) | DE58904128D1 (en) |
ES (1) | ES2040503T3 (en) |
WO (1) | WO1990001460A1 (en) |
ZA (1) | ZA896027B (en) |
Families Citing this family (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
AT398967B (en) * | 1992-03-10 | 1995-02-27 | Veitsch Radex Ag | METHOD FOR PRODUCING A FINE-PART OXIDE POWDER |
JPH0656506A (en) * | 1992-06-05 | 1994-03-01 | Veitscher Magnesitwerke Ag | Production of ceramic material and its molding using finely powdered fire-proofing oxide |
US5569684A (en) * | 1994-03-03 | 1996-10-29 | Takita Patent & Engineering | Heat conductive silicone rubber composition |
EP0807092B1 (en) * | 1995-01-31 | 2001-04-11 | Robert Bosch Gmbh | Method of producing ceramic powders with a surface which is made hydrophobic and their use |
DE19547183A1 (en) * | 1995-01-31 | 1996-08-01 | Bosch Gmbh Robert | Ceramic powders with a hydrophobic surface and their manufacture and use |
DE19502891A1 (en) * | 1995-01-31 | 1996-08-01 | Bosch Gmbh Robert | Molding compound |
US6179897B1 (en) | 1999-03-18 | 2001-01-30 | Brookhaven Science Associates | Method for the generation of variable density metal vapors which bypasses the liquidus phase |
WO2001030699A1 (en) * | 1999-10-25 | 2001-05-03 | Nedmag Industries Mining & Manufacturing B.V. | Magnesium oxide, a mixture of metal oxides, methods for preparation thereof and the use of the materials as frac proppant |
WO2005046830A2 (en) * | 2003-11-12 | 2005-05-26 | Watts Regulator Co. | Zero waste reverse osmosis water filtering |
JP5773110B2 (en) * | 2013-05-24 | 2015-09-02 | 堺化学工業株式会社 | Magnesium oxide particles, method for producing magnesium oxide particles, resin composition, and molded article, adhesive or grease using the resin composition |
EP3126289B1 (en) * | 2014-04-01 | 2023-06-07 | Purac Biochem bv | Thermal decomposition of magnesium chloride |
JP6739627B2 (en) * | 2017-03-28 | 2020-08-12 | 宇部マテリアルズ株式会社 | Coated magnesium oxide particles, method for producing the same, and thermally conductive resin composition |
Family Cites Families (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
AT150622B (en) * | 1935-01-10 | 1937-09-10 | Magnesit Ind Aktien Ges | Process for the production of temperature change resistant magnesite bricks. |
BE755184A (en) * | 1969-08-25 | 1971-02-01 | Oesterr Amerikan Magnesit | REFRACTORY FIRED MAGNESITE BRICK, AND PROCESS FOR ITS MANUFACTURING |
NL174953C (en) * | 1970-11-24 | 1984-09-03 | Degussa | METHOD FOR HYDROPHOBICIZING METAL OR SILICON OXIDES |
AT352081B (en) * | 1977-08-22 | 1979-08-27 | Veitscher Magnesitwerke Ag | PROCESS FOR THE LARGE-SCALE PRODUCTION OF METAL OXIDES, IN PARTICULAR MAGNESIUM OXIDE, AND DEVICE FOR CARRYING OUT THE PROCESS |
US4298379A (en) * | 1980-01-31 | 1981-11-03 | The Hanna Mining Company | Production of high purity and high surface area magnesium oxide |
AT376416B (en) * | 1981-06-05 | 1984-11-26 | Veitscher Magnesitwerke Ag | METHOD FOR ADAPTING FIRE-RESISTANT MOLDED BODIES WITH APPROXIMATELY VERTICAL MATCHING SURFACES IN HOT OVEN LININGS AND FIRE-RESISTANT MEASURES FOR IMPLEMENTING THE METHOD |
JPS59227765A (en) * | 1983-06-04 | 1984-12-21 | 科学技術庁金属材料技術研究所長 | Manufacture of ceramic super fine particle |
JPS60166260A (en) * | 1984-02-10 | 1985-08-29 | 旭硝子株式会社 | Mgo sintered body for insulator substrate and manufacture |
JPS60200824A (en) * | 1984-03-27 | 1985-10-11 | Shin Nippon Kagaku Kogyo Co Ltd | Magnesia and its production |
AT382142B (en) * | 1984-12-17 | 1987-01-12 | Ruthner Michael Johann Dipl In | METHOD AND DEVICE FOR PRODUCING CERAMIC POWDERS BASED ON ONE AND / OR MULTI-COMPONENT METAL OXIDS, AND MIXTURES THEREOF |
DD236081A1 (en) * | 1985-04-11 | 1986-05-28 | Kali Veb K | METHOD FOR PRODUCING A BRIKETTING-PROOF MAGNESIUM OXIDE POWDER |
JPS61270213A (en) * | 1985-05-27 | 1986-11-29 | Shin Nippon Kagaku Kogyo Co Ltd | Modified magnesia and production thereof |
JPH0776126B2 (en) * | 1986-06-03 | 1995-08-16 | 神島化学工業株式会社 | Method for manufacturing magnesia sintered body |
JPS6345117A (en) * | 1986-08-08 | 1988-02-26 | Ube Ind Ltd | Production of magnesia powder resistant to hydration |
-
1988
- 1988-08-10 AT AT2006/88A patent/AT392464B/en not_active IP Right Cessation
-
1989
- 1989-08-03 DE DE8989890206T patent/DE58904128D1/en not_active Expired - Fee Related
- 1989-08-03 KR KR1019900700747A patent/KR900701660A/en not_active Application Discontinuation
- 1989-08-03 AT AT89890206T patent/ATE88446T1/en not_active IP Right Cessation
- 1989-08-03 JP JP1508668A patent/JPH064487B2/en not_active Expired - Lifetime
- 1989-08-03 AU AU40636/89A patent/AU619885B2/en not_active Ceased
- 1989-08-03 ES ES198989890206T patent/ES2040503T3/en not_active Expired - Lifetime
- 1989-08-03 EP EP89909119A patent/EP0404867A1/en active Pending
- 1989-08-03 EP EP89890206A patent/EP0354896B1/en not_active Expired - Lifetime
- 1989-08-03 BR BR898907050A patent/BR8907050A/en not_active Application Discontinuation
- 1989-08-03 US US07/490,572 patent/US5106608A/en not_active Expired - Fee Related
- 1989-08-03 WO PCT/AT1989/000069 patent/WO1990001460A1/en not_active Application Discontinuation
- 1989-08-08 ZA ZA896027A patent/ZA896027B/en unknown
- 1989-08-08 CA CA000607716A patent/CA1334156C/en not_active Expired - Fee Related
Non-Patent Citations (1)
Title |
---|
See references of WO9001460A1 * |
Also Published As
Publication number | Publication date |
---|---|
AT392464B (en) | 1991-04-10 |
EP0354896B1 (en) | 1993-04-21 |
KR900701660A (en) | 1990-12-04 |
JPH03501380A (en) | 1991-03-28 |
ATA200688A (en) | 1990-09-15 |
EP0354896A2 (en) | 1990-02-14 |
BR8907050A (en) | 1991-01-02 |
AU4063689A (en) | 1990-03-05 |
EP0354896A3 (en) | 1990-03-14 |
ZA896027B (en) | 1990-05-30 |
WO1990001460A1 (en) | 1990-02-22 |
DE58904128D1 (en) | 1993-05-27 |
ATE88446T1 (en) | 1993-05-15 |
JPH064487B2 (en) | 1994-01-19 |
CA1334156C (en) | 1995-01-31 |
AU619885B2 (en) | 1992-02-06 |
ES2040503T3 (en) | 1993-10-16 |
US5106608A (en) | 1992-04-21 |
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Free format text: VERFAHREN ABGESCHLOSSEN INFOLGE VERBINDUNG MIT 89890206.9/0354896 (EUROPAEISCHE ANMELDENUMMER/VEROEFFENTLICHUNGSNUMMER) VOM 14.01.92. |