Abstract: Novel methods for processing fumed metallic oxides into globular metallic oxide agglomerates are provided. The methodology may allow for fumed metallic oxide particles, such as fumed silica and fumed alumina particles, to be processed into a globular morphology to improve handling while retaining a desirable surface area. The processes may include providing fumed metallic oxide particles, combining the particles with a liquid carrier to form a suspension, atomizing the solution of suspended particles, and subjecting the atomized droplets to a temperature range sufficient to remove the liquid carrier from the droplets, to produce metallic oxide-containing agglomerations.

Abstract: One aspect relates to a method for the production of synthetic quartz glass. Moreover, one aspect relates to a polyalkylsiloxane compound, which includes certain specifications with respect to chlorine content, metallic impurities content, and residual moisture, as well as the use thereof for the production of synthetic quartz glass. One aspect also relates to a synthetic quartz glass that can be obtained according to the method of one embodiment.

Abstract: Provided are novel electrode material composite structures containing high capacity active materials formed into porous base structures. The structures also include shells that encapsulate these porous base structures. During lithiation of the active material, the shell mechanically constrains the porous base structure. The shell allows lithium ions to pass through but prevents electrolyte solvents from interacting with the encapsulated active material. In certain embodiments, the shell contains carbon, while the porous base structure contains silicon. Although silicon tends to swell during lithiation, the porosity of the base structure and/or void spaces inside the shell helps to accommodate this additional volume within the shell without breaking it or substantially increasing the overall size of the composite structure.

Abstract: The invention relates to a method for producing synthetic quartz glass by vaporizing a polyalkylsiloxane as a liquid SiO2 feedstock (105), converting the vaporized SiO2 feedstock (107) into SiO2 particles, separating the SiO2 particles, forming a soot body (200) and vitrifying the soot body (200). According to the invention, the vaporizing of the heated SiO2 feedstock (105) comprises an injection phase in an expansion chamber (125), in which the SiO2 feedstock (105) is atomized into fine droplets, wherein the droplets have an average diameter of less than 5 pm, and wherein the atomizing of the droplets takes place in a preheated carrier gas stream which has a temperature of more than 180° C.

Abstract: Disclosed is a flame reactor characterized in that the flame reactor comprises a reactor chamber having a volume of 1 m3 to 10 m3, is 1 m to 10 m high, and includes a reactor nozzle for feeding the reactants.

Abstract: Polycrystalline silicon rods produced by the Siemens process produce a higher yield of CZ crystals when the process parameters are modified in a second stage of deposition such that an outer layer of larger crystallites having a mean swize>20 ?m is produced. Harvesting of these polycrystalline rods and conventional rods by enclosing them in a plastic bag or sheath prior to removal from the reactor also surprisingly increase the yield of CZ crystals grown from a melt containing the sheathed rods.

Abstract: To provide a process for producing a dispersion of hollow fine SiO2 particles which contains no residual core fine particles, generates no uncontrollable agglomerates, and is easy to filtrate.

Abstract: The invention relates to silicon dioxide powder which is present in the form of aggregated primary particles having an average diameter of at least 40 nm and a ratio of the BET surface area to the STSA surface area of at least 3.5. The invention also relates to a toner composition containing said silicon dioxide powder.

Abstract: Methods, systems, and apparatus are disclosed herein for recovery of high-purity silicon, silicon carbide and PEG from a slurry produced during a wafer cutting process. A silicon-containing material can be processed for production of a silicon-rich composition. Silicon carbide and PEG recovered from the silicon-containing material can be used to form a wafer-saw cutting fluid. The silicon-rich composition can be reacted with iodine containing compounds that can be purified and/or used to form deposited silicon of high purity. The produced silicon can be used in the photovoltaic industry or semiconductor industry.

Abstract: A large scale process for preparing fumed silica with consistent product parameters wherein a silica precursor compound is fed to a burner at ?100 Kg/h along with a combusting gas at ?300 m3/h and a combustible gas at ?100 m3/h, with a nozzle gas velocity between 10 and 200 m/s, and a radially symmetrical, homogenous gas velocity and gas temperature.

Abstract: A method of producing a range of diatomaceous earth filter aids having selectable permeabilities and less than about 1 percent by weight total crystalline silica. The method includes milling diatomaceous earth ore to a size range of between about 100 micrometers and about 1400 micrometers; calcining the milled diatomaceous earth in a calciner; and milling the calcined diatomaceous earth in an adjustable milling and classification system to produce diatomaceous earth filter aids. Systems to implement such methods and compositions produced by such methods are also described.

Abstract: The invention provides fumed silica comprising aggregates that have an aggregate size and a surface area that satisfy particular formulas relating aggregate size to surface area, as well as aggregates that exhibit particular viscosity, power law exponent index, and/or elastic modulus characteristics when dispersed in liquid media. The invention also provides processes of preparing such fumed silica by combining a silica precursor with a stream of combustible gas, combusting the stream, and producing a stream of combusted gas and fumed silica particles, wherein dopants are introduced, the time/temperature profile, or history, of the stream of combusted gas and fumed silica particles is adjusted to allow for post-quench aggregate growth, and/or additional silica precursor is introduced into the stream of combusted gas.

Abstract: Hexachlorodisilane is decomposed into hydrochloric acid, silicon dioxide and water by introducing hexachlorodisilane-containing flue gas into a reaction region without moistening the flue gas and by supplying oxygen-containing gas that also contains a small amount of moisture to the reaction region maintained at a temperature at which hexachlorodisilane decomposes.

Abstract: Silicon titanium mixed oxide powder having the following features: BET surface area of 5 to 300 m2/g, silica content, based on the total amount of the mixed oxide powder, of ?0.1 to <0.5% by weight, titanium dioxide content, based on the total amount of the mixed oxide powder, of ?99.0% by weight, sum of the proportions of silica and titanium dioxide, based on the total amount of the mixed oxide powder, ?99.5% by weight, titanium dioxide content of the primary particles comprising intergrown rutile and anatase phases, silica content of the primary particles amorphous, is prepared by allowing the vapours of one or more, in each case oxidizable and/or hydrolyzable titanium and silicon compounds to react in a high temperature zone with oxygen and/or steam, cooling the reaction mixture after the reaction and separating off the pulverulent solid from gaseous substances.

Abstract: The invention provides a process for the production of fumed silica. The process comprises providing a silicon halide feedstock comprising about 80% to 100% methyltrichlorosilane, combining the silicon halide feedstock with hydrogen gas and oxygen gas to form a reactant mixture, discharging the reactant mixture out of a burner, and combusting the hydrogen gas and the oxygen gas of the reactant mixture so as to hydrolyze the silicon halide feedstock to produce fumed silica. Hydrogen (H2) is present in a mole fraction of about 0.11 or less based on the reactant mixture, and/or the velocity of the reactant mixture upon exiting the burner is about 25 m/s or more.

Abstract: Stable, aqueous dispersion containing silicon dioxide powder having a hydroxyl group density of 2.5 to 4.7 OH/nm2, which is obtained from a silicon dioxide powder produced by a flame hydrolysis process under acid conditions. The dispersion is produced by incorporating the silicon dioxide powder into an aqueous solution by means of a dispersing device. The dispersion can be used to produce glass articles.

Abstract: Stable, aqueous dispersion containing silicon dioxide powder having a hydroxyl group density of 2.5 to 4.7 OH/nm2, which is obtained from a silicon dioxide powder produced by a flame hydrolysis process under acid conditions. The dispersion is produced by incorporating the silicon dioxide powder into an aqueous solution by means of a dispersing device. The dispersion can be used to produce glass articles.

Abstract: The present invention provides for evaporation induced self-assembly (EISA) within microdroplets produced by a vibrating orifice aerosol generator (VOAG) for the production of monodisperse mesoporous silica particles. The process of the present invention exploits the concentration of evaporating droplets to induce the organization of various amphiphilic molecules, effectively partitioning a silica precursor to the hydrophilic regions of the structure. Promotion of silica condensation, followed by removal of the surfactant, provides ordered spherical mesoporous particles.

Abstract: Provided is a pyrogenically prepared SiO2 powder in the form of aggregated primary particles having a statistical thickness surface area (STSA) of 10-500 m2/g, a thickening action based on the STSA of 4-8 mPas·g/m2, and a micropore volume of 0.03-0.

Abstract: Stable, aqueous dispersion containing silicon dioxide powder having a hydroxyl group density of 2.5 to 4.7 OH/nm2, which is obtained from a silicon dioxide powder produced by a flame hydrolysis process under acid conditions. The dispersion is produced by incorporating the silicon dioxide powder into an aqueous solution by means of a dispersing device. The dispersion can be used to produce glass articles.

Abstract: Highly pure pyrogenic silica is produced in an integrated polycrystalline silicon production plant by separating offgas from polycrystalline silicon production into a high boiler fraction, vaporizing this fraction into a pyrogenic silica burner and reacting with air and/or oxygen and hydrogen to form pyrogenic silica.

Abstract: There is provided a method of preparing silica (SiO2) nanoparticles from siliceous mudstone which is silica mineral sources, using a chemical reaction. The method of preparing silica nanoparticles from siliceous mudstone comprises: solving a silica constituent into a sodium silicate aqueous solution by a sodium hydroxide leaching reaction of the siliceous mudstone (S100); performing ion exchange to remove a sodium constituent from the sodium silicate aqueous solution and to prepare a silicate aqueous solution (S200); and performing flame spray pyrolysis to prepare silica nanoparticles with an average particle dimension being in a range of 9 to 57 nm from the silicate aqueous solution.

Abstract: Process for removing halide compounds adhering to finely divided metal oxide particles by means of steam, wherein the metal oxide particles are applied to the upper part of an upright column and migrate downwards by means of gravity, the steam is applied at the bottom end of the column, the metal oxide particles and the steam are fed counter-currently, the metal oxide particles freed of halide residues are removed at the base of the column, steam and halide residues are removed at the head of the column, wherein the column is heated in such a manner that the temperature difference Tbottom?Ttop between the lower part and the upper part of the column is at least 20° C. and a maximum temperature of 500° C. prevails in the column, and the metal oxide particles have a residence time in the column of from 1 second to 30 minutes.

Abstract: The invention relates to a process for the preparation of a titanium catalyst which process comprises: (a) drying a silica carrier at a temperature of from 300 to 800° C. to obtain a dried carrier; (b) contacting the dried carrier obtained in step (a) with a gas stream containing titanium halide at a temperature in the range from 125° C. lower to 125° C. higher than the drying temperature of step (a) and at a pressure higher than 0.8 bar to obtain an impregnated carrier; (c) calcining the impregnated carrier obtained in step (b) to obtain the titanium catalyst.

Abstract: Pyrogenic silicon dioxide powder with a BET surface area of 30 to 90 m2/g, a DBP index of 80 or less, a mean aggregate area of less than 25000 nm2 and a mean aggregate circumference of less than 1000 nm, wherein at least 70% of the aggregates have a circumference of less than 1300 nm. It is prepared by mixing at least one silicon compound in vapor form, a free-oxygen-containing gas and a combustible gas in a burner of known construction, igniting this gas mixture at the mouth of the burner and burning it in the flame tube of the burner, separating the solid obtained from the gas mixture and optionally purifying, wherein the oxygen content of the free-oxygen-containing gas is adjusted so that the lambda value is greater than or equal to 1, the gamma value is between 1.2 and 1.8, the throughput is between 0.1 and 0.3 kg SiO2/m3 of core gas mixture and the mean normalized rate of flow of gas in the flame tube at the level of the mouth of the burner is at least 5 m/s. The powder can be used as a filler.

Abstract: Silica particles and compositions containing silica particles are disclosed. Methods of making silica particles and methods of using silica particles are also disclosed.

Abstract: The invention provides fumed silica comprising aggregates that have an aggregate size and a surface area that satisfy particular formulas relating aggregate size to surface area, as well as aggregates that exhibit particular viscosity, power law exponent index, and/or elastic modulus characteristics when dispersed in liquid media. The invention also provides processes of preparing such fumed silica by combining a silica precursor with a stream of combustible gas, combusting the stream, and producing a stream of combusted gas and fumed silica particles, wherein dopants are introduced, the time/temperature profile, or history, of the stream of combusted gas and fumed silica particles is adjusted to allow for post-quench aggregate growth, and/or additional silica precursor is introduced into the stream of combusted gas.

Abstract: A method of preparing channel-type mesoporous material with an elliptical pore section is described. An alkaline solution containing two surfactants different in the electronic properties of their hydrophilic groups is prepared. A silica precursor is added to form a stack of rod-like micelles each having an elliptical section with the silica precursor between the rod-like micelles. The silica precursor is reacted into a silica framework. The rod-like micelles are removed from the silica framework.

Abstract: Pyrogenic metal oxides having consistent quality and consistency between batches are prepared by flame hydrolysis in a reactor whose walls are cooled to below 500° C.

Abstract: By using a halogen-free siloxane and an organometallic compound containing at least one metal other than silicon as feed stocks, and simultaneously atomizing and burning them in a flame, spherical particles of silica-containing compound oxide are prepared which are substantially halogen-free, consist of 0.5-99% by weight of metal oxides and the balance of silica, and have a particle size of 10 nm to 3 ?m. The particles are useful as a filler in epoxy resin base semiconductor sealants, a refractive index modifier or the like.

Abstract: There is provided particulate silica which can be suitably used as a viscoelasticity modifier such as a thickener which is added to liquid such as water, a liquid resin or paint to adjust its viscoelastic properties such as viscosity and thixotropic nature, a reinforcer or filler for silicone rubber or sealants, a polishing agent for CMP (Chemical Mechanical Polishing) or a surface coating agent for ink-jet printing paper. The particulate silica has a BET specific surface area S of 130 to 380 m2/g, and its fractal shape parameter ?1 in an ?-value analysis target range of 20 to 30 nm satisfies the following equation (1) and its fractal shape parameter ?2 in an ?-value analysis target range of 30 to 50 nm satisfies the following equation (2). ?1+0.00175S<2.518??(1) ?2+0.00174S<2.

Abstract: A highly pure ultra-fine SiOx (wherein x is from 0.6 to 1.8) powder having a specific surface area of at least 10 m2/g and a total content of Na, Fe, Al and Cl of at most 10 ppm is provided. The SiOx powder is produced by reacting a monosilane gas with a gas capable of oxidizing the monosilane gas in a non-oxidizing gas atmosphere under a pressure of from 10 to 1000 kPa at a temperature of from 500 to 1000° C. In this case, the amount of the non-oxidizing gas is preferably larger than the total amount of the monosilane gas and oxygen participating in the oxidation of the gas capable of oxidizing the monosilane gas.

Abstract: A production process for producing high-purity silica from a crude silica source by means of fluosilic acid, including the steps of: (a) subjecting the crude silica souce and the fluosilicic acid to a reaction in a reaction stage, so as to produce silicon tetrafluoride and water; (b) selectively evaporating the silicon tetrafluoride with respect to at least a portion of at least one impurity derived from the crude silica source, and (c) reacting the silicon tetrafluoride with water to produce the high-purity silica, wherein the reaction stage (a) is performed at a temperature above 75° C.

Abstract: 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.

Abstract: The invention relates to a method for making silica nanoparticles using a flame reactor, which includes a droplet spray having a two-fluid nozzle and a burner of a quintuple tube structure. In this method, droplets of silicon alkoxide as liquid Si compound are sprayed through the droplet spray of the flame reactor. A flame is generated by the flow of inert gas, oxygen, hydrogen and air simultaneously into the burner of the flame reactor. The liquid Si compound is delivered through the flame of the burner to produce silica nanoparticles having a mean particle size ranging from 9 nm to 68 nm. Resultant nanoparticles are collected and recovered in a particle collector. The droplets sprayed under high pressure from a silicon alkoxide solution are directly oxidized in the flame, thereby producing spherical silica nanoparticles.

Abstract: A hydrophobic fumed silica treated with a cyclic dimethylsiloxane, the hydrophobic fumed silica having an M-value representing an oleophilic degree in a range of 48 to 65, a tapping bulk density of not smaller than 80 g/L but not larger than 130 g/L, and an n-value representing the dispersion of 3.0 to 3.5 as measured in toluene. The hydrophobic fumed silica features a high bulk density while exhibiting a high hydrophobic property, the powder thereof capable of being favorably handled, being easily mixed in a matrix such as of a resin within short periods of time, and, further, being dispersed in the matrix to a high degree.

Abstract: Highly pure pyrogenic silica is produced in an integrated polycrystalline silicon production plant by separating offgas from polycrystalline silicon production into a high boiler fraction, vaporizing this fraction into a pyrogenic silica burner and reacting with air and/or oxygen and hydrogen to form pyrogenic silica.

Abstract: Provided is a pyrogenically prepared SiO2 powder in the form of aggregated primary particles having a statistical thickness surface area (STSA) of 10-500 m2/g, a thickening action based on the STSA of 4-8 mPas·g/m2, and a micropore volume of 0.03-0.

Abstract: A kinetically controlled vapor reaction process for synthesizing silica areogel in a reaction container by injection of a precursor reagent vapor, a catalyst reagent vapor, super saturated steam as a component of the catalyst solution, and a hydrophobic reagent vapor amd continuously mixing vapor droplets of the precursor, catalyst and water reagents in a super saturated state to continuously nucleate in a hydrolysis/poly-condensation reaction and deposit as silica aerogel.

Abstract: A silicon oxide powder can be continuously prepared by feeding a raw material powder mixture containing silicon dioxide powder into a reaction chamber (2) at a temperature of 1,100-1,600° C., to produce a silicon oxide gas, transferring the silicon oxide gas to a deposition chamber (11) through a transfer conduit (10) maintained at a temperature of from higher than 1,000° C. to 1,300° C., causing silicon oxide to deposit on a substrate (13) which is disposed and cooled in the deposition chamber, scraping the silicon oxide deposit, and recovering the deposit in a recovery chamber (18). The method and apparatus is capable of continuous and stable production of amorphous silicon oxide powder of high purity.

Abstract: A mesoporous material is described. It includes a network of interconnected pores within an L3 phase structure. The pores include pore walls of a silicate material functionalized with at least one metal cation—usually a transition metal. Articles which include the mesoporous material are also disclosed, along with methods for making the mesoporous material.

Abstract: A hydrophobic silica fine powder is prepared by premixing a hydrophilic silica fine powder with a dimer diol siloxane or cyclic siloxane as a hydrophobizing agent, mixing them in a ball mill for achieving dispersion and for achieving cleavage or disintegration and consolidation, and thereafter heating at 100-300° C. in an ammonia or amine-containing atmosphere. The powder has an aerated bulk density of 100-300 g/l, a specific surface area of 40-300 m2/g, a primary particle diameter of 10-120 nm, and a degree of hydrophobization of 40-80 as measured by methanol titration and is less bulky, easy to handle and disperse and stable in a kneaded mixture.

Abstract: A fumed-silica, which can make a slurry having sufficient wettability to a polar liquid, excellent dispersibility, and low viscosity even in the high concentration, and a slurry thereof. A fumed-silica and its slurry are provided, wherein the water content is controlled so that a weight loss after drying Y, and a dynamic wetting rate to water Z, have specified values.

Abstract: A high concentration silica slurry can be used for polishing of substrates, such as semiconductor materials. The slurry contains a silica powder dispersed in an solvent. The silica slurry has a silica concentration of more than 50% by weight and a viscosity of less than 1000 mPa·s, wherein the silica powder has a ratio DL/DT of less than 1.3, wherein DL is an average particle size of the silica powder measured by a laser diffraction particle size distribution method and DT is an average primary particle size of the silica powder measured by a TEM photography observation, and wherein the silica powder has an average primary particle size of from 0.08 ?m to 0.8 ?m.

Abstract: A method for the production of inorganic aluminum substances and amorphous silica from aluminum oxide containing ores, comprising: (a) leaching of said ores with fluorosilicic acid to obtain aluminum fluosilicate solution; (b) filtering said leached solution from insoluble materials; and (c) washing said insoluble materials.

Abstract: The amorphous-silica particle having 0.1–0.7 ?m of the average particle diameter, 5–30 m2/g of the specific surface area, less than 40% of the dispersion coefficient, and 20 ?C/m2 of the absolute value of the triboelectrostatic charge, can be obtained, by setting flame temperature to more than melting point of silica, raising the silica concentration in a flame, and staying the generated silica particle in the flame for a short time to be grew up. Since this silica particle has a particle shape being near a true sphere, and a particle size of said particle is remarkably uniform, so it is suitable for a filler of a semiconductor sealing agent or various materials, etc. In addition, since said particle has strong electrification, it is also suitable for an outer or an inner additional agent of a toner for an electronic photograph, a photo conductor material for a electronic photograph, and a material of an electric charge transportation layer, etc.

Abstract: A surface modified fine silica powder which has been treated, preferably, with a treating agent containing an amino group, characterized in that the powder exhibits an adsorption amount for an anion source compound of 150% or more of that of an original powder which has not been treated; and a printing material using the silica powder. The surface modified fine silica powder can provide an excellent printed matter being free from blotting with ink or a cracking of coating film.

Abstract: Particulate silica is prepared by feeding a gas mixture of an organohalosilane gas, a flammable gas capable of generating water vapor when burned, and a free oxygen-containing gas to a reaction chamber through a multiple-tube burner, whereby the organohalosilane is subjected to flame hydrolysis and oxidation reaction. The amount of the flammable gas fed is 0.5-9 mol per mol of the organohalosilane and such that the amount of water vapor resulting from combustion of the flammable gas is 1-6 times the stoichiometric amount, and the gas mixture is fed to the center tube of the burner such that it may have a linear velocity at the outlet of 50-120 m/sec, calculated in the standard state. The resulting silica has a surface area of 100-400 m2/g and a narrow particle size distribution of primary particles and ensures the transparency of silicone rubber filled therewith.

Abstract: This invention relates to the production of high purity fused silica glass through oxidation or flame hydrolysis of a vaporizable silicon-containing compound. More particularly, this invention is directed to the use of vaporizable, halide-free compounds in said production. In the preferred practice, a polymethylsiloxane comprises said vaporizable, halide-free compound.

Abstract: This invention pertains to surfactant-templated nanometer-scale porosity of a silica precursor solution and forming a mesoporous material by first forming the silica precursor solution into a preform having a high surface area to volume ratio, then rapid drying or evaporating a solvent from the silica precursor solution. The mesoporous material may be in any geometric form, but is preferably in the form of a film, fiber, powder or combinations thereof. The rapid drying or evaporation of solvent from the solution is accomplished by layer thinning, for example spin casting, liquid drawing, and liquid spraying respectively. Production of a film is by layer thinning, wherein a layer of the silica precursor solution is formed on a surface followed by removal of an amount of the silica precursor solution and leaving a geometrically thinner layer of the silica precursor solution from which the solvent quickly escapes via evaporation.