A boron nitride powder, containing at least an aggregated boron nitride particle formed by an aggregation of hexagonal boron nitride primary particles, the powder having a particle size distribution including at least a first maximum point, a second maximum point at which a particle size is larger than at the first maximum point, and a third maximum point at which a particle size is larger than at the second maximum point. The heat dissipation sheet is obtained by molding a heat conductive resin composition containing the boron nitride powder and a resin. The method for producing a heat dissipation sheet includes blending the boron nitride powder and a resin to prepare a heat conductive resin composition, molding the heat conductive resin composition into a sheet shape to prepare a heat conductive resin composition sheet, and heating and pressurizing the heat conductive resin composition sheet under a vacuum.

The present disclosure relates to an alumina having a surface area in the range of 330-400 m.sup.2/g, a pore volume in the range of 1.2-1.7 cc/g, and an average pore diameter in the range of 125-160 . The present disclosure also relates to alumina extrudates having a diameter in the range of 1 mm to 3 mm, a surface area in the range of 300-360 m.sup.2/g, a pore volume in the range of 0.8-1.3 cc/g and pore diameter in the range of 90-130 with a crushing strength in the range of 1-2.5 daN/mm. Further, the present disclosure relates to a process for the preparation of alumina and alumina extrudates. The alumina extrudates can be used as a support for catalyst preparation or as a catalyst or adsorbent in various processes. The process of the present disclosure enhances metal loading capacity, has better metal dispersion, and exhibit delay in deactivation of the catalyst due to mouth pore plugging.

A method for producing potassium chloride granular materials from a crystalline potassium chloride raw material, wherein, before the granulation process, the potassium chloride raw material is treated with at least one alkali metal carbonate and at least one metaphosphate additive in the presence of water

A method for producing potassium chloride granular materials from a crystalline potassium chloride raw material, wherein, before the granulation process, the potassium chloride raw material is treated with at least one alkali metal carbonate and at least one hydrogen phosphate additive in the presence of water. The alkali metal carbonate is anhydrous sodium carbonate, sodium carbonate monohydrate or sodium carbonate decahydrate.

A method for producing potassium chloride granulates from a crystalline potassium chloride raw material. The potassium chloride raw material is treated, prior to granulation, with at least one alkali metal carbonate and at least one phosphate additive selected from alkali metal monophosphates, alkali metal pyrophosphates, linear alkali metal polyphosphates and mixtures thereof, in the presence of water.

Porous silicon and methods for preparation and use of the same are disclosed. The porous silicon materials have utility either alone or in combination with other materials, for example, combined with carbon particles for energy storage applications.

Provide is a porous spherical silica useful as a polish and as a cosmetic material. The porous spherical silica is such that less impurities are contained therein, the particle size distribution thereof is narrow, the D50 thereof is within a predetermined range, and the pore volume thereof is within a predetermined range, the D50 thereof is 2 to 200 m, the D10/D90 thereof is at least 0.3, the pore volume thereof is 0.5 mL/g to 8 mL/g, the arithmetic mean value of the breaking compressive test forces of specimens of ten particles is 1.010.sup.1 to 1.010.sup.2 mN, and the alkali metal content thereof is at most 50 ppm. The porous spherical silica can be produced by forming a W/O emulsion using a fumed silica dispersion as an aqueous phase, and pH-adjusting or heating to gelate this emulsion, and thereafter collecting and drying the resultant.

An alumina composite sol composition includes (A) an alumina sol containing an alumina hydrate, (B) an alkoxysilane compound, (C) a polyvalent organic acid, and (D) a solvent, wherein the amount of the alumina hydrate in the alumina sol (A) is 3 to 11% by mass.

A complex oxide powder contains cerium and aluminum, and has a specific surface area of 0.5 m.sup.2/g or more and 10 m.sup.2/g or less.

A lithium metal composite oxide powder includes primary particles; and secondary particles formed by aggregation of the primary particles, in which the lithium metal composite oxide powder is represented by Composition Formula (1), and the lithium metal composite oxide powder satisfies all of requirements (A), (B), and (C).