摘要:
Pyrogenically produced silica after separation of the hydrogen halide is mixed with nitrogen and conveyed into a cyclone. After separation of the gases, which are returned into the cooling stretch of the production apparatus, the silica is first mixed with organohalosilane and nitrogen and subsequently with steam and nitrogen. Subsequently the hydrophobization reaction is carried out in known manner in a fluidized bed reactor. The reaction waste gases are returned into the cyclone.
摘要:
Surface-modified, doped, pyrogenically produced oxides surface-modified with one or several compounds from the following groups: a) Organosilanes of the type (RO)3Si(CnH2n+1), (RO)3Si(CnH2n−1) b) R′x(RO)ySi(CnH2n+1), (RO)3Si(CnH2n+1) c) X3Si(CnH2n+1), X3Si(CnH2n−1) d) X2(R′)Si(CnH2n+1), X2(R′)Si(CnH2n−1) e) X(R′)2Si(CnH2n+1), X(R′)2Si(CnH2n−1) f) (RO)3Si(CH2)m—R′, g) (R″)x(RO)ySi(CH2)m—R′, h) X3Si(CH2)m—R′, i) (R)X2Si(CH2)m—R′, j) (R)2XSi(CH2)m—R′, k) Silazanes of the type l) Cyclic polysiloxanes, m) Polysiloxanes or silicone oils.
摘要翻译:表面改性,掺杂,热解产生的氧化物用一种或几种来自以下组的化合物进行表面改性:a)类型(RO)3 Si(C n) H 2 n + 1),(RO)3 Si(C n H 2n-1)b)R (RO)y y y y y>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> 3 Si(C n H 2n + 1)c)X 3 Si(C n H n) H 2n + 1),X 3 Si(C n H 2n-1)d)X -R',j)(R)2 XSi(CH 2)m -R a,k)1)的硅氮烷, C 聚硅氧烷,m)聚硅氧烷或硅油。
摘要:
Pyrogenically produced silicon dioxide powder in the form of aggregates of primary particles having a BET surface area of 200±25 m2/g, wherein the aggregates display an average surface area of 7000 to 12000 nm2, an average equivalent circle diameter (ECD) of 80 to 100 nm and an average circumference of 850 to 1050 nm. It is produced by a pyrogenic process in which silicon tetrachloride and a second silicon component comprising H3SiCl, H2SiCl2, HSiCl3, CH3SiCl3, (CH3)2SiCl2, (CH3)3SiCl and/or (n-C3H7)SiCl3 are mixed with primary air and a combustion gas and burnt into a reaction chamber, secondary air also being introduced into the reaction chamber, and the feed materials being chosen such that an adiabatic flame temperature of 1570 to 1630° C. is obtained. It can be used as a filler.
摘要:
A boron oxide-silicon dioxide mixed oxide which has a BET surface of less than 100 m.sup.2 g, and optionally containing oxides of aluminium, titanium or zirconium, is prepared pyrogenically by flame hydrolysis. The mixed oxide is used in glass making.
摘要:
Flame-hydrolytically produced titanium dioxide mixed oxide having a BET surface of 10 to 150 m.sup.2 /g and 1 to 30% by weight aluminum oxide or 1 to 30% by weight silicon dioxide is produced by evaporating aluminum chloride or silicon tetrachloride, transferring the evaporated aluminum chloride or silicon tetrachloride, together with an inert gas, into the mixing chamber of a burner, mixing them with hydrogen, air and gaseous titanium tetrachloride, burning the resulting 4-component mixture in the reaction chamber of the burner, and separating the titanium dioxide mixed oxide from the gaseous reaction products.
摘要:
Finely divided precipitated silica for use as a delustering agent with high structure and a______________________________________ BET surface (DIN 66 132) of 150 to 350 m.sup.2 /g Stamping density (DIN 53 194) between 60 and 120 g/l DBP absorption number between 3.0 and 4.0 ml/g Particle size distribution at least 70% from 1 to 6 .mu.m ______________________________________ can be prepared by heating a mixture of water and sodium silicate under agitation to a temperature of 70.degree. to 80.degree. C., adding concentrated sulfuric acid into this mixture until half of the alkali present has been neutralized, shearing the reaction mixture and optionally raising the temperature at the same time to 86.degree..+-.5.degree. C. Concentrated sulfuric acid is added after a period of 30 to 120 minutes at a rather high rate until the pH of the silica suspension produced is 3.0 to 3.5. The resulting silica suspension is ultimately filtered off by known filter devices, the silica filter cake washed free of sulfate, and a dry product is ultimately obtained.
摘要:
Process for the phase transformation of substances and mixtures of substances, in which the substance or the mixture of substances is introduced into a plasma reactor, the substance or the mixture of substances is converted into the higher-energy phase and the product is removed in gaseous form from the plasma reactor. The process can be used for the sublimation of metal salts, metal nitrates and/or metal alkoxides and other vaporizable metal-organic compounds.
摘要:
Pyrogenically produced silicon dioxide powder with a specific surface area of between 5 and 600 m2/g and a carbon content of less than 500 ppm, which displays a specific dibutyl phthalate absorption of less than or equal to 1.2 g dibutyl phthalate/100 g SiO2 per m2 of specific surface area and a specific thickening action of less than 15 mPas/m2 of specific surface area. It is produced by supplying vaporous tetramethoxysilane and/or tetraethoxysilane together with air and separately hydrogen to a burner, and allowing the mixture of gases to react in a flame in a reaction chamber connected in series to the burner, and separating the solid reaction product from the gas stream by known means, the lambda value in the burner being between 0.95 and 1.5 and sufficient secondary air also being supplied to the reaction chamber that the lambda value in the reaction chamber is between 0.8 and 1.6. The invention also provides a dispersion containing the silicon dioxide powder and the use of the powder and of the dispersion.
摘要翻译:比热表面积为5〜600m 2 / g,碳含量小于500ppm的热解生成二氧化硅粉末,其特征在于邻苯二甲酸二丁酯的吸收小于或等于1.2 g二丁基邻苯二甲酸酯/ 100g SiO 2 / m 2比表面积和特定增稠作用小于15mPas / m 2比表面积。 它是通过将空气四甲氧基硅烷和/或四乙氧基硅烷与空气和单独的氢气一起向燃烧器供应的,并且允许气体混合物在与燃烧器串联连接的反应室中的火焰中反应,并将固体反应产物从 通过已知方式的气流,燃烧器中的λ值在0.95和1.5之间,并且足够的二次空气也被供应到反应室,反应室中的λ值在0.8和1.6之间。 本发明还提供了含有二氧化硅粉末的分散体以及粉末和分散体的用途。
摘要:
A toner or a mixture of toners, comprises a pyrogenically synthesized alumina-silica mixed oxide as a component in combination with other components necessary to complete a toner formulation. The surface of the mixed alumina-silica oxide material.
摘要:
A toner or a mixture of toners, comprises a pyrogenically synthesized alumina-silica mixed oxide as a component in combination with other components necessary to complete a toner formulation. The surface of the mixed alumina-silica oxide material.