Abstract: Silica-based hydrophobic granular material with an increased polarity Silica-based granular material, comprising silica and at least one IR-opacifier, hydrophobized with a surface treatment agent comprising a silicon atom, wherein the granular material has: a) a cumulative pore volume of pores>4 nm of more than 2.5 cm3/g, as determined by the mercury intrusion method according to DIN ISO 15901-1; b) a tamped density of 140 g/L to 290 g/L; c) a number of silanol groups relative to BET surface area dSiOH of at least 0.5 SiOH/nm2, as determined by reaction with lithium aluminium hydride. d) a number of silicon atoms in the surface treatment agent relative to BET surface area d[Si] of at least 1.0 [Si atoms]/nm2.

Abstract: Surface-treated fumed silica, with a tribo-electro static charge of ?500 ?C/g to +500 ?C/g, a ratio of the tribo-electro static charge to BET surface area of ?3.5 ?C/m2 to +3.5 ?C/m2, a methanol wettability of at least 20% by volume methanol in methanol/water mixture, a ratio of carbon content to BET surface area of at most 0.020 wt. %*g/m2, a process for its preparation and the use thereof.

Abstract: The invention provides fumed silica granules having a BET surface area of 20 m2/g to 500 m2/g; a number average particle size d50 of 350 ?m to 2000 ?m; a span (d90?d10)/d50 of particle size distribution of 0.8-3.0; a bulk density of more than 0.35 g/mL; a pore volume for pores >4 nm of not more than 1.5 cm3/g, process for its preparation and use thereof as a catalyst carrier, a carrier for liquid substances, in cosmetic applications, for thermal insulation, as pharmaceutical excipient, in producing thermally treated silica granules, as an abrasive, as a component of a silicone rubber.

Abstract: Dry mixture comprising: (a) from 10% to 99% by weight of a precipitated silica having: (a1) BET surface area of from 30 m2/g to 700 m2/g, (a1) numerical median particle size d50 determined by laser diffraction method of from 100 ?m to 600 ?m, (a3) silanol group density dSiOH determined by reaction of the pre-dried silica with lithium aluminum hydride of from 1.55 to 3.65 SiOH/nm2 and (b) from 1 wt % to 90 wt % of at least one organic compound: (b1) selected from selected from an alcohol, a diol, an aldehyde, a ketone, a carboxylic acid, a carboxylic esters, a nitrate ester, an amine, and/or oxygen and/or nitrogen heterocycle, (b2) having 2 to 12 carbon atoms, (b3) having a vapour pressure of at least 0.01 kPa at 293 K, wherein the organic compound is adsorbed on the precipitated silica, the process for manufacturing thereof.

Abstract: Process for catalytic oxidative esterification of methacrolein with methanol and oxygen to methyl methacrylate in the presence of a heterogeneous egg-shell catalyst comprising gold metal and an oxide of at least one second element selected from Ni, Co, Fe, Zn and/or Ti supported on a support material comprising SiO2, Al2O3 and at least one basic element oxide, characterized in that the process is carried out in the presence of at least one compound, comprising Ni, Co, Fe, Zn and/or Ti, which is soluble in the reaction mixture under process conditions.

Abstract: A process for producing at least one pyrogenic compound can be performed. A burner suitable for use in said process has at least four concentric tubes, where a second tube is arranged around the central tube. A process for making the burner can be performed, and a production facility that has at least one burner can be made.

Abstract: Fumed alumina powder with reduced moisture content Surface unmodified fumed alumina powder comprising less than 5% by weight of alpha-Al2O3, as determined by XRD analysis, having a numerical average particle size d50 of less than 5 ?m, as determined by SLS, and a ratio R150=KF150/BET of the water content KF150, as determined by Karl Fischer titration method after drying of the fumed alumina powder at 150° C. for 2 hours, to its BET surface area of not more than 0.0122 wt %×g/m2, preparation method and the use thereof.

Abstract: A curable composition for production of coatings for thermal, electrical and/or acoustic insulation, where the composition has at least one aqueous binder can be made. The composition has a first component based on spray-dried fumed silica pellets. The composition also has at least one second component selected from the group of the silicon dioxides, preferably microsilica, pellets based on pyrogenically produced silicon dioxide, silica aerogels, silicate glass (foamed glass/expanded glass), hollow silicon dioxide particles (hollow glass beads), or pellets selected from perlites, preferably expanded perlites, vermiculites, polymers, preferably expanded polystyrene pellets, and mixtures thereof.

Abstract: Process for producing fumed silica powder with a decreased silanol group density, comprising subjecting a fumed surface untreated silica powder with a silanol density dSiOH of at least 1.2 SiOH/nm2 and a particle size d90 of not more than 10 ?m, to thermal treatment at a temperature of 350° C. to 1250° C. for 5 min to 5 h, wherein the temperature and the duration of the thermal treatment are chosen so that dSiOH of the silica is decreased by 10%-70% relative to dSiOH of the employed thermally untreated silica, wherein the thermal treatment is carried out while the fumed silica powder is in motion, followed by optional surface treatment. Surface unmodified and modified fumed silica powders obtained by this process and the use thereof.

Abstract: Methacrolein is prepared in a continuous process by a Mannich condensation reaction of formaldehyde with propanal. A methacrolein polymerization inhibitor is introduced during the production process and a part thereof is recycled back into the reactor where the Mannich condensation reaction is carried out.

Abstract: The invention provides fumed silica granules having a BET surface area of 20 m2/g to 500 m2/g; a number average particle size d50 of 350 ?m to 2000 ?m; a span (d90?d10)/d50 of particle size distribution of 0.8-3.0; a bulk density of more than 0.35 g/mL; a pore volume for pores >4 nm of not more than 1.5 cm3/g, process for its preparation and use thereof as a catalyst carrier, a carrier for liquid substances, in cosmetic applications, for thermal insulation, as pharmaceutical excipient, in producing thermally treated silica granules, as an abrasive, as a component of a silicone rubber.

Abstract: The invention relates to a process for preparing a carboxylic ester by reacting an aldehyde in the presence of an aluminum alkoxide, wherein the aluminum alkoxide is obtained either by reacting an aluminum hydride with an aldehyde or by reacting a different aluminum alkoxide with a carboxylic ester.

Abstract: The present invention relates to a process for producing silica-based thermal insulation moulded body comprising at least 50% by weight of synthetic amorphous silica and not more than 50% by weight of natural silica with a specified particle size, thermal insulation moulded body obtainable by this process and the use thereof for thermal and/or acoustic insulation.

Abstract: Fumed silica powder, surface treated with a surface treatment agent selected from the group consisting of organosilanes, silazanes, acyclic polysiloxanes, cyclic polysiloxanes, and mixtures thereof, wherein the powder has: a) a number of silanol groups relative to BET surface area dSiOH of at least 0.85 SiOH/nm2, as determined by reaction with lithium aluminium hydride; b) a methanol wettability of more than 40% by volume of methanol in methanol-water mixture; c) a tamped density of not more than 200 g/L.

Abstract: Silica-based hydrophobic granular material with an increased polarity Silica-based granular material, comprising silica and at least one IR-opacifier, hydrophobized with a surface treatment agent comprising a silicon atom, wherein the granular material has: a) a cumulative pore volume of pores>4 nm of more than 2.5 cm3/g, as determined by the mercury intrusion method according to DIN ISO 15901-1; b) a tamped density of 140 g/L to 290 g/L; c) a number of silanol groups relative to BET surface area dSiOH of at least 0.5 SiOH/nm2, as determined by reaction with lithium aluminium hydride. d) a number of silicon atoms in the surface treatment agent relative to BET surface area d[Si] of at least 1.0 [Si atoms]/nm2.

Abstract: Surface-treated fumed silica, with a tribo-electro static charge of ?500 ?C/g to +500 ?C/g, a ratio of the tribo-electro static charge to BET surface area of ?3.5 ?C/m2 to +3.5 ?C/m2, a methanol wettability of at least 20% by volume methanol in methanol/water mixture, a ratio of carbon content to BET surface area of at most 0.020 wt. %*g/m2, a process for its preparation and the use thereof.

Abstract: Methacrolein is prepared in a continuous process by a Mannich condensation reaction of formaldehyde with propanal. A methacrolein polymerization inhibitor is introduced during the production process and a part thereof is recycled back into the reactor where the Mannich condensation reaction is carried out.

Abstract: The present invention relates to a novel process for performing a heterogeneously catalyzed reaction for oxidative esterification of aldehydes to give carboxylic esters. Against this background, it has been possible by the present process according to the invention to perform such processes for longer periods without disruption, with constant or even increased activities and selectivities. This gives rise to the possibility of performing such processes in a very simple, economically viable and environmentally benign manner.

Abstract: The invention relates to a process for preparing a carboxylic ester by reacting an aldehyde in the presence of an aluminum alkoxide, wherein the aluminum alkoxide is obtained either by reacting an aluminum hydride with an aldehyde or by reacting a different aluminum alkoxide with a carboxylic ester.

Abstract: The invention relates to a process for preparing a carboxylic ester by reacting an aldehyde in the presence of an aluminum alkoxide, wherein the aluminum alkoxide is obtained either by reacting an aluminum hydride with an aldehyde or by reacting a different aluminum alkoxide with a carboxylic ester.