A method for producing new nanomaterials, 80 to 100 mol % of which are composed of TiO.sub.2 and 0 to 20 mol % are composed of another metal or semi-metal oxide that has a specific surface of 100 to 300 m.sup.2.g.sup.1and 1 to 3 hydroxyl groups per nm.sup.2.

A process of making a dense, cohesive and uniform aluminum oxide coating on a metallic substrate includes electrodepositing polynuclear aluminum oxide hydroxide clusters from a polynuclear aluminum oxide hydroxide cluster solution on a metallic substrate to form a precursor coating, and post-treating the precursor coating to form a final aluminum oxide coating on the metallic substrate.

A process of making a dense, cohesive and uniform aluminum oxide coating on a metallic substrate includes electrodepositing polynuclear aluminum oxide hydroxide clusters from a polynuclear aluminum oxide hydroxide cluster solution on a metallic substrate to form a precursor coating, and post-treating the precursor coating to form a final aluminum oxide coating on the metallic substrate.

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 negative electrode active material for a non-aqueous electrolyte secondary battery, includes: negative electrode active material particles that contain a silicon compound (SiO.sub.x: 0.5?x?1.6) containing a Li compound, wherein the silicon compound is at least partially coated with a carbon coating, and at least a part of a surface of the silicon compound, a surface of the carbon coating, or both of them are coated with a composite layer that contains a composite composed of amorphous metal oxide and metal hydroxide. This provides a negative electrode active material for a non-aqueous electrolyte secondary battery that is highly stable in aqueous slurry, having a high capacity, favorable cycle performance and first efficiency.

A negative electrode active material for a non-aqueous electrolyte secondary battery, includes: negative electrode active material particles that contain a silicon compound (SiO.sub.x: 0.5?x?1.6) containing a Li compound, wherein the silicon compound is at least partially coated with a carbon coating, and at least a part of a surface of the silicon compound, a surface of the carbon coating, or both of them are coated with a composite layer that contains a composite composed of amorphous metal oxide and metal hydroxide. This provides a negative electrode active material for a non-aqueous electrolyte secondary battery that is highly stable in aqueous slurry, having a high capacity, favorable cycle performance and first efficiency.

A sintered compact has a first material, a second material, and a third material. The first material is cubic boron nitride. The second material is a compound including zirconium. The third material is an aluminum oxide and the aluminum oxide includes a fine-particle aluminum oxide. The sintered compact has a first region in which not less than 5 volume % and not more than 50 volume % of the fine-particle aluminum oxide is dispersed in the second material. On arbitrary straight lines in the first region, an average value of continuous distances occupied by the fine-particle aluminum oxide is not more than 0.08 m and a standard deviation of the continuous distances occupied by the fine-particle aluminum oxide is not more than 0.1 m.

A method of producing a highly-pure aluminum hydroxide, comprising the following steps: (1) reacting alcohol with metal aluminum to produce aluminum alkoxide, then hydrolyzing the aluminum alkoxide with water to produce an aluminum hydroxide slurry and an alcohol, filtering the aluminum hydroxide slurry, washing a resulting filter cake with water to remove the alcohol trapped therein, and drying the filter cake after the water washing to produce an aluminum hydroxide powder, (2) sending the alcohol-containing water produced in step (1) to an alcohol extraction unit for separating water and alcohol through extraction, and sending the separated water back to step (1) for recycling, (3) dehydrating the hydrous alcohol produced by hydrolyzing the aluminum alkoxide in step (1) before using it as the raw materials for reacting metal aluminum with alcohol to produce aluminum alkoxide in step (1). The method can improve the recovery of alcohol, reduce the production cost of a highly-pure aluminum hydroxide, improve the purity of aluminum oxide and achieve a zero discharge of sewage by recycling water.

A sintered compact has a first material, a second material, and a third material. The first material is cubic boron nitride. The second material is a compound including zirconium. The third material is an aluminum oxide and the aluminum oxide includes a fine-particle aluminum oxide. The sintered compact has a first region in which not less than 5 volume % and not more than 50 volume % of the fine-particle aluminum oxide is dispersed in the second material. On arbitrary straight lines in the first region, an average value of continuous distances occupied by the fine-particle aluminum oxide is not more than 0.08 m and a standard deviation of the continuous distances occupied by the fine-particle aluminum oxide is not more than 0.1 m.

The present invention relates to a calcined shaped alumina and to a method of preparing a calcined shaped alumina. The method comprises that the alumina in the alumina suspension is hydrothermally aged to have a specific crystallite size. This in turn produces a highly stable alumina in the form of a calcined shaped alumina particularly at temperatures of 1200 C. and above.