Abstract: Process for the production of aluminum hydroxide flame-retardants by wet-miling and spray-drying an aluminium hydroxide containing slurry.

Abstract: The present invention relates to methods of producing surface-modified nanoparticulate particles at least of one metal oxide, metal hydroxide and/or metal oxide hydroxide, and aqueous suspensions of these particles. The invention further relates to the surface-modified nanoparticulate particles, obtainable by these methods, at least of one metal oxide, metal hydroxide and/or metal oxide hydroxide and aqueous suspensions of these particles, and to their use for cosmetic sunscreen preparations, as stabilizer in plastics and as antimicrobial active ingredient.

Abstract: A method for producing a particulate alumina composition includes the steps of preparing a wet particulate in a gas-liquid-solid three-phase system containing air by adding water and/or one or more compounds selected from an inorganic compound and an oxygen-containing organic compound to one or more alumina sources selected from an alumina hydrate and an alumina being rehydratable in the temperature range of 70 to 250° C., and to carry out a hydrothermal reaction in a temperature range of 70° C. to 250° C. Filtration and washing are carried out after the particulate alumina composition is preliminarily brought into contact with an alkaline component when an acid component is removed from the particulate alumina composition. The particulate alumina composition obtained by the method has a specific surface area in a dried product at 200° C. in the range of 40 to 300 m2/g and contains crystalline boehmite having an aspect ratio of 10 or less.

Abstract: The present invention relates to a process for the production of aluminum hydroxide flame retardants. The process involves the after-treatment of aluminum hydroxide through the use of mill-drying and deagglomeration.

Abstract: The present invention relates to a process for the production of aluminum hydroxide flame retardants having improved thermal stability, the aluminum hydroxide particles produced therefrom, the use of the aluminum hydroxide particles produced therefrom, and articles therefrom.

Abstract: The present invention relates to a novel process for the production of aluminum hydroxide flame retardants having improved thermal stability, the aluminum hydroxide particles produced therefrom, the use of the aluminum hydroxide particles produced therefrom in flame retarded polymer formulations, and molded or extruded articles made from the flame retarded polymer formulations.

Abstract: The present invention relates to a novel process for the production of aluminum hydroxide flame retardants having improved thermal stability, the aluminum hydroxide particles produced therefrom, the use of the aluminum hydroxide particles produced therefrom in flame retarded polymer formulations, and molded or extruded articles made from the flame retarded polymer formulations.

Abstract: A static ion-exchange process for the preparation of a polynuclear Al species comprising the treatment of an aqueous aluminium chloride solution with a hydroxide-form ion-exchange resin at a temperature of from 5° C. to 60° C. for a period of at least 30 minutes.

Abstract: An alumina particle (1) of the present invention has an alumina body with a short axis length (b) of 1 to 10 nm, a long axis length (a) of 20 to 400 nm and an aspect ratio (a/b) of 5 to 80. The alumina body is expressed by a Formula I, and n is not less than 0. Al2O3.

Abstract: The present invention provides gibbsite type aluminum hydroxide particles having a primary particle diameter of from 0.01 ?m to 0.3 ?m and a DOP oil absorption of from 90 mL/100 g to 300 mL/100 g.

Abstract: A reinforcing aluminum-based filler which can be used for reinforcing diene rubber compositions intended for the manufacture of tires, comprising an aluminum (oxide-)hydroxide corresponding, with the exception of any impurities and the water of hydration, to the general formula (a and b being real numbers): Al(OH)aOb, with 0<a?3 and b=(3?a)/2, ??(I) the specific BET surface area of which is between 30 and 400 m2/g, the average particle size (by mass) dw of which is between 20 and 400 nm and the disagglomeration rate, ?, of which, measured via an ultrasound disagglomeration test at 100% power of a 600-watt ultrasonic probe, is greater than 5×10?3 ?m?1/s is provided. A rubber composition suitable for the manufacture of tires comprising said aluminum-based filler as reinforcing filler.

Abstract: The invention is a device for purifying drinking water that has at least one fibrous structure. Preferably, there is an upstream and downstream fibrous structure. Each fibrous structure is a mixture of nano alumina fibers and second fibers arranged in a matrix to create asymmetric pores and to which fine, ultrafine, or nanosize particles are attached. Preferably, the device has an upstream antimicrobial for sterilization of retained microbes. The device is substantially more efficient at removing soluble contaminants such as halogens from a fluid stream than those previously available and is also able to retain turbidity, bacteria, and virus.

Abstract: Methods of making unique water treatment compositions are provided. In one embodiment, a method of making a doped metal oxide or hydroxide for treating water comprises: disposing a metal precursor solution and a dopant precursor solution in a reaction vessel comprising water to form a slurry; and precipitating the doped metal oxide or hydroxide from the slurry.

Abstract: The invention is a filter for gaseous media in which nano alumina fibers and second fibers are arranged in a matrix to create asymmetrical pores. The filter is a high efficiency, high capacity particulate filter that intercepts pathogens and other particulate matter from gaseous media, including vapor-suspended particles. The new filter has an improved retention of water-aerosolized particles as compared to conventional HEPA filters and may be used as a pre-filter that extends the life of HEPA filters by about five to ten times. The invention is also a method of manufacturing and using the filter.

Abstract: Provided are methods of preparing a separator for an electrochemical cell comprising the steps of (a) coating onto a substrate a liquid mixture comprising an inorganic oxide, an organic polymer, a divinyl ether of an ethylene glycol, and/or an organic carbonate; (b) drying the coating; and (c) delaminating the coating from the substrate to form the separator comprising an inorganic oxide and the organic polymer, wherein the inorganic oxide of step (c) comprises a reaction product of the divinyl ether and/or the organic carbonate with the inorganic oxide of step (a). Preferably, the inorganic oxide of step (c) comprises a hydrated aluminum oxide of the formula Al2O3.H2O, wherein x is less than 1.0, and wherein the hydrated aluminum oxide comprises a reaction product of the divinyl ether and/or organic carbonate with the inorganic oxide of step (a), such as pseudo-boehmite.

Abstract: A method for producing aluminum hydroxide includes a step of elevating a temperature of a slurry of aluminum hydroxide suspended in a sodium aluminate solution from 70° C. or lower to 85° C. or higher, and a step of applying a centrifugal force to the slurry. The aluminum hydroxide constituting the slurry is obtained beforehand through the Bayer's process.

Abstract: The present invention pertains to a quasi-crystalline boehmite containing additive in a homogeneously dispersed state. Suitable additives are compounds containing elements selected from the group of alkaline earth metals, alkaline metals, rare earth metals, transition metals, actinides, silicon, gallium, boron, titanium, and phosphorus. Said QCBs according to the invention may be prepared in several ways. In general, a quasi-crystalline boehmite precursor and an additive are converted to a quasi-crystalline boehmite containing the additive in a homogeneously dispersed state.

Abstract: A flame retardant polymer composition consists of a) 20–60 percent by weight of a thermoplastic and/or cross-linked or cross-linkable elastomer and b) as a flame retardant agent 40–80 percent by weight either of an aluminum hydroxide with the material values specific surface according to BET 3–5 mg2/g mean grain size d50 1.0–1.5 ?m residual moisture 0.1–0.4% oil absorption 19–23% water absorption 0.4–0.6 ml/g or of an aluminum hydroxide with the material values specific surface according to BET 5–8 m2/g mean grain size d50 0.8–1.3 ?m residual moisture 0.1–0.6% oil absorption 21–25% water absorption 0.6–0.8 ml/g. A process of producing the flame retardant agent is characterised in that a filter-moist aluminum hydroxide obtained by precipitation and filtration with a mean grain size of 0.8 to 1.5 ?m is subjected to mill drying in a turbulent hot air stream in such a way that, while the grain distribution is largely retained, the BET surface is increased by at least 20%.

Abstract: A method for producing aluminum hydroxide, comprises the steps of: elevating a temperature of a slurry having agglomerated secondary particles of aluminum hydroxide obtained through the Bayer's process suspended in a sodium aluminate solution from not more than 70° C. to not less than 85° C. within 15 minutes, thereby disintegrating the agglomerated secondary particles; and retaining, for a period of at least 15 minutes from temperature elevation, the temperature of the slurry so as not to be lowered to not less than 80° C.

Abstract: A composition of matter which is aluminum hydroxide, produced using the Bayer Process, wherein the aluminum hydroxide produced has a Total Organic Carbon of less than about 0.5 milligrams Total Organic Carbon/gram aluminum hydroxide.

Abstract: A method for producing a hydrorefining catalyst is used to produce the hydrorefining catalyst which contains an inorganic oxide carrier and a hydrogenation-active metal and which has such a bimodal pore characteristic that pores having pore diameters of not more than 50 nm have a pore volume of not less than 0.4 cm3/g, pores having pore diameters of not less than 50 nm have a pore volume of not less than 0.2 cm3/g, and pores having pore diameters of not less than 1000 nm have a pore volume of not more than 0.1 cm3/g. The method comprises the steps of mixing and forming a pseudo-boehmite powder having a dispersibility index of 0.13 to 0.28, and calcinating the formed pseudo-boehmite under a condition in which the pseudo-boehmite is converted into ?-alumina. The hydrorefining catalyst, which has the bimodal pore characteristic, can be produced easily at low cost.

Abstract: Gibbsite type aluminium hydroxides are obtained by seeding a Bayer liquor with bayerite crystals. The gibbsite type aluminium hydroxide show excellent properties as fire retardant fillers in synthetic resins.

Abstract: In a BAYER circuit, a process for controlling precipitation in which particle size quality of alumina hydrate produced in the circuit and circulating in feed tanks is monitored utilizing a calibration step and a control step. In the calibration step, cumulative percentage of alumina hydrate particles circulating in the feed tanks in the circuit that are finer than X2 ?m, defined as CPFT X2, is measured vs. time and cumulative percentage of alumina hydrate particles circulating in the feed tanks in the circuit that are finer that X1 ?m, defined as CPFT X1 vs. time, is measured, where X1 and X2 are predetermined particles sizes and X1 is smaller than X2. A relationship R between CPFT X1 and later changes in CPFT X2, is determined and upper and lower trigger thresholds of CPFT X1 which correspond to maximum permissible variation in CPFT X2 are defined. In the control step, CPFT X1 and CPFT X2 are regularly measured, and R and the correlation between CPFT X2 and the particle size of hydrate produced are updated.

Abstract: Aluminum hydroxide fibers approximately 2 nanometers in diameter and with surface areas ranging from 200 to 650 m2/g have been fount to be highly electropositive. When dispersed in water they are able to attach to and retain electronegative particles. When combined into a composite filter with other fibers or particles they can filter bacteria and nano size particulates such as viruses and colloidal particles at high flux through the filter. Such filters can be used for purification and sterilization of water, biological, medical and pharmaceutical fluids, and as a collector/concentrator for detection and assay of mirobes and viruses. The alumina fibers are also capable of filtering sub-micron inorganic and metallic particles to produce ultra pure water. The fibers are suitable as a substrate for growth of cells. Macromolicules such as proteins may be separated from each other based on their electronegative charges.

Abstract: A composition of matter which is aluminum hydroxide, produced using the Bayer Process, wherein the aluminum hydroxide produced has a Total Organic Carbon of less than about 0.5 milligrams Total Organic Carbon/gram aluminum hydroxide.

Abstract: Aluminium hydroxide of high whiteness is produced by (i) heating aluminium hydroxide obtained from the Bayer process to a temperature of 300 to 700° C. (ii) dissolving the soluble fraction of the thus obtained activated product at 85 to 275° C. in aqueous sodium hydroxide to form a sodium aluminate liquor containing an undissolved residue of very fine boehmite, (iii) filtering said sodium aluminate liquor to obtain a clear solution of sodium aluminate supersaturated with respect to dissolved alumina, (iv) cooling said clear solution to 50 to 80° C. and seeding with crystallized aluminium hydroxide to induce further crystallization, and (v) separating, washing and drying the produced aluminium hydroxide crystals.

Abstract: The invention pertains to new catalyst systems for polycondensation reactions, for example for producing polyethylene terephthalate. In accordance with the invention, complex compounds with hydrotalcite-analogous structures of general formula [M(II)1−xM(III)x(OH)2]x+(An−x/n).mH2O are used, wherein M(II) represents divalent metals, preferably Mg or Zn or NI or Cu or Fe(II) or Co, and M(III) represents trivalent metals, for example Al or Fe(III), and A represents anions, preferably carbonates or borates. These catalysts can be calcinated and can be used in combination with phosphorus compounds that contain at least one hydrolyzable phosphorus-oxygen bond.

Abstract: Thermally stable transitional alumina particulates retaining high specific surface area after calcination at 1000° C. suitable for the use as catalysts or catalysts supports are produced by treating an aqueous solution containing Al3+ and optionally a doping amount of La3+ (e.g., 0.3 mol. %) with an anion-exchange resin to give a stable hydroxide sol followed by freeze drying of the sol and further thermal dehydration. The resultant stabilized transitional alumina retains high specific surface area at 1000° C., and additionally stabilization is achieved at very low levels of added La.

Abstract: The invention relates to a method for the production of aluminium oxide hydrate containing crystals, whereby a liquid aluminium oxide hydrate phase is brought into contact with an auxiliary agent phase containing an organic auxiliary agent having at least one of the following properties:

Abstract: A method for producing aluminum hydroxide includes elevating, from 70° C. or lower to 85° C. or higher within 15 minutes, a temperature of a slurry of aluminum hydroxide suspended in a sodium aluminate solution, which aluminum hydroxide has been obtained through the Bayer's process, and then maintaining the temperature of the slurry, without being lowered to 80° C. or lower, for at least 15 minutes from temperature elevation initiation.

Abstract: A dispersion of alumina hydrate comprises an alumina hydrate containing 0.1 to 1.0% by weight of a nitrate anion and having an average pore radius of 20 to 200 Å and a half breadth of pore radius distribution of 20 to 150 Å and deionized water. Another dispersion of alumina hydrate comprises an alumina hydrate containing 0.1 to 1.0% by weight of a nitrate anion and having at least two peaks in pore radius distribution and deionized water. Another dispersion of alumina hydrate comprises a titanium dioxide-containing alumina hydrate containing 0.1 to 1.0% by weight of a nitrate anion and deionized water. In each of these dispersions, when the alumina hydrate is dispersed in water at a solids concentration of 15% by weight to form a dispersion, the viscosity of the dispersion is not higher than 75 cP as measured at 20° C. and the dispersion has a shear rate of 7.9 sec−1.

Abstract: The invention relates to a method for producing a stable aluminium hydroxide gel on the basis of the sodium aluminate lye which is obtained during the production of Al2O3 according to the BAYER method. The caustic mol ratio (Na2Ofree/Al2O3) of the lye containing aluminate is adjusted to smaller than 1.6. The lye is treated with carboxylic acid anhydride, whereby the aluminium hydroxide gel is precipitated at a temperature of below approximately 40° C., whereby the pH value ranges from 8 to 12. The precipitation product and the lye are separated from one another. The precipitation product is washed and dried, whereby the amorphous structure is obtained.

Abstract: A method for producing aluminum hydroxide includes a step of elevating a temperature of a slurry of aluminum hydroxide suspended in a sodium aluminate solution from 70° C. or lower to 85° C. or higher, and a step of applying a centrifugal force to the slurry. The aluminum hydroxide constituting the slurry is obtained beforehand through the Bayer's process.

Abstract: A reinforcing aluminum-based filler which can be used for reinforcing diene rubber compositions intended for the manufacture of tires, comprising an aluminum (oxide-)hydroxide corresponding, with the exception of any impurities and the water of hydration, to the general formula (a and b being real numbers): Al(OH)aOb, with 0<a≦3 and b=(3-a)/2,  (I) the specific BET surface area of which is between 30 and 400 m2/g, the average particle size (by mass) dw of which is between 20 and 400 nm and the disagglomeration rate, &agr;, of which, measured via an ultrasound disagglomeration test at 100% power of a 600-watt ultrasonic probe, is greater than 5×10−3 &mgr;m−1/s is provided. A rubber composition suitable for the manufacture of tires comprising said aluminum-based filler as reinforcing filler.

Abstract: Aluminium hydroxide of improved thermal stability is produced by spray-drying of an aqueous slurry of aluminium hydroxide at 400 to 600° C. drying gas temperature. The resulting aluminium hydroxide is suitable as a flame retardant filler in polymeric systems with high processing temperatures. It has a low specific surface area and good rheological properties.

Abstract: A method for making alumina having a pore structure characterized by the absence of macropores, no more than 5% of the total pore volume in pores greater than 350 Å, a high pore volume (greater than 0.8 cc/g measured by mercury intrusion) and a bi-modal pore volume distribution character, where the two modes are separated by 10 to 200 Å, and the primary pore mode is larger than the median pore diameter (MPD), calculated either by volume or by surface area, the MPD by volume being itself larger than the MPD by surface area. Alumina made by such process and catalyst made therefrom.

Abstract: Aluminum hydroxide aggregated particles which have an average particle diameter of not less than 40 &mgr;m, an average particle diameter as determined after pressing at 1,000 kg/cm2 of not more than 35 &mgr;m, and an L value of slurry obtained by mixing 20 ml of glycerol and 10 g of the aluminum hydroxide aggregated particles of not more than 69, are obtained by a process comprising the steps of:

Abstract: A microcrystalline boehmite containing additive in a homogeneously dispersed state. Suitable additives are compounds containing elements selected from the group consisting of alkaline earth metals, alkaline metals, rare earth metals, transition metals, actinides, silicon, gallium, boron, titanium, and phosphorus. The microcrystalline boehmite according to the invention may be prepared in several ways. In general, a microcrystalline boehmite precursor and an additive are converted to a microcrystalline boehmite containing the additive in a homogeneously dispersed state. The additive does not contain zirconia or magnesia.

Abstract: Method for the preparation of a laminate for printed circuit boards by composing together surface layers of curable resin impregnated woven glass fabric and intermediate layers of curable resin impregnated non-woven glass. The intermediate layers contain 200 percent by weight to 275 percent by weight, based on the resin in the intermediate layers, of a thermally stable aluminum hydroxide of the molecular formula Al2O3.nH2O, wherein n has a value of 2.6<n<2.9. The aluminum hydroxide has a specific surface area, measured by the BET method, of 2 to 10 m2/g and a particle size in the D50% range of 5 to 10 &mgr;m.

Abstract: A process for producing alumina from bauxite is described in which bauxite is treated with an alkali to form a mixture comprising a solution of aluminum-containing ions and alumina trihydrate is precipitated from the solution. The process comprises treatment of the solution before or after the precipitation step with a layered double hydroxide in order to remove impurities from the solution by intercalation into the layers in the double hydroxide. The double hydroxide may contain layers of the formula: [LiAl2(OH)6]+.

Abstract: Laminates for printed circuit boards having surface layers of curable resin impregnated woven glass fabric and intermediate layers of curable resin impregnated non-woven glass. The intermediate layers contain 200 percent by weight to 275 percent by weight, based on the resin in the intermediate layers, of a thermally stable aluminum hydroxide of the molecular formula Al2O3.nH2O, wherein n has a value of 2.6<n<2.9. The aluminum hydroxide has a specific surface area, measured by the BET method, of 2 to 10 m2/g and a particle size in the D50% range of 5 to 10 &mgr;m.

Abstract: Mesoporous crystalline alumina compositions and process for the preparation thereof are described. The compositions are useful as catalysts and absorbents.

Abstract: Printed circuit boards of a laminate having surface layers of curable resin impregnated woven glass fabric and intermediate layers of curable resin impregnated non-woven glass. The intermediate layers contain 200 percent by weight to 275 percent by weight, based on the resin in the intermediate layers, of a thermally stable aluminum hydroxide of the molecular formula Al2O3.nH2O, wherein n has a value of 2.6<n<2.9. The aluminum hydroxide has a specific surface area, measured by the BET method, of 2 to 10 m2/g and a particle size in the D50% range of 5 to 10 &mgr;m.

Abstract: Printed circuit board laminates which have improved thermal stability. The improved properties are attributed to the use of a novel aluminium hydroxide which is described by the molecular representation: Al2O3·nH2O where n>2.6 and <2.9.

Abstract: A phase of aluminum trihydroxide and supports and catalysts made therefrom. This invention also relates to methods of producing this phase of aluminum trihydroxide and catalysts made therefrom, and to a method for improving the activity of and for regenerating catalysts having a silica-alumina support.

Abstract: An aluminum hydroxide having high purity with high brightness and a method for producing such an aluminum hydroxide are provided. The aluminum hydroxide may be produced by a method which comprises the steps of mixing a crude aluminum hydroxide with an alkaline solution to obtain a mixture thereof; heating the mixture to obtain a slurry in which a solid of aluminum hydroxide is present in an amount of from about 10% by weight to about 90% by weight based on the crude aluminum hydroxide to be used for the mixing; cooling the slurry to precipitate an aluminum hydroxide; and separating the resulting aluminum hydroxide from the slurry.

Abstract: The present invention pertains to a quasi-crystalline boehmite containing additive in a homogeneously dispersed state. Suitable additives are compounds containing elements selected from the group of alkaline earth metals, alkaline metals, transition metals, actinides, silicon, gallium, boron, titanium, and phosphorus. Said QCBs according to the invention may be prepared in several ways. In general, a quasi-crystalline boehmite precursor and an additive are converted to a quasi-crystalline boehmite containing the additive in a homogeneously dispersed state.

Abstract: The present invention provide a boehmite in which (i) a crystallite diameter in the direction perpendicular to the plane (020) is about 65 angstrom or longer and (ii) a ratio of a crystallite diameter in the direction perpendicular to the plane (002) to a crystallite diameter in the direction perpendicular to the plane (200) is about 1.8 or more. By using the boehmite as a non-magnetic pigment, a base coat layer for magnetic recording medium having an excellent surface smoothness can be obtained.

Abstract: Production of an alumina powder characterized by having a single or multiple crystal structure selected from the group consisting of &ggr;, &dgr; and &thgr;-forms, a primary particle size of 10 to 50 nm, a mean secondary particle size of 100 to 500 nm, and a granular primary particle shape, or an alumina powder characterized by having an a-form crystal structure, a primary particle size of 60 to 150 nm, a mean secondary particle size of 200 to 500 nm, and a granular primary particle shape, using as a raw material an alumina hydrate comprising rectangular plate-like primary particles having a boehmite structure and having a length of one side of 10 to 50 nm; and preparation of a polishing composition comprising the alumina powder, water and a polishing accelerator.

Abstract: Pseudo-boehmite, which is a raw material for a catalyst carrier for hydrogenation refining, is produced by mixing, under a predetermined condition, an aluminate aqueous solution produced from an alkaline etching step for aluminum in an alumite treatment and an acidic aluminum aqueous solution produced from an anodization step for aluminum in the alumite treatment. Pseudo-boehmite can be also produced by maturing, with an alkaline solution, an aluminum hydroxide sludge produced from a washing step for aluminum in the alumite treatment. It is possible to establish a method for producing pseudo-boehmite, which makes it possible to reutilize a resource at extremely low cost by utilizing a treatment waste liquid and a sludge in an alumite treatment site.