A hydroconversion catalyst with a bimodal pore structure: an oxide matrix predominantly of calcined aluminium; a hydro-dehydrogenative active phase of at least one group VIII metal being at least partly commixed within the said oxide matrix mainly made up of calcined aluminium, an S.sub.BET specific surface greater than 100 m.sup.2/g, a mesoporous median diameter in volume between 12 and 25 nm inclusive, a macroporous median diameter in volume between 250 and 1500 nm inclusive, a mesoporous volume as measured by mercury intrusion porosimeter greater than or equal to 0.55 ml/g and a total measured pore volume by mercury porosimetry greater than or equal to 0.70 ml/g;
a method for preparing a residue catalyst for hydroconversion/hydroprocessing by commixing the active phase with a particular alumina,
the use of the catalyst in hydroproces sing, including hydroproces sing heavy feeds.

A novel alumina gel is described having an elevated dispersibility index, and in particular a dispersibility index greater than 70%, a crystallite size between 1 and 35 nm, and a sulphur content between 0.001% and 2% by weight, and a sodium content between 0.001% and 2% by weight, the weight percentages being expressed in relation to the total mass of alumina gel.

The present invention also discloses the method for preparing said gel comprising at least one step of precipitating at least one aluminium salt, at least one step of heating the suspension obtained and a final heat treatment step for forming the alumina gel.

The present invention relates to -Al.sub.2O.sub.3 flakes prepared by a process comprising (1) preparation of an aqueous solution of at least one water-soluble and/or insoluble aluminum salt which optionally contains at least one sulfate compound, (2) adding a basic solution and optionally at least one dopant to the aluminum salt solution (1), (3) drying of the obtained gel, followed by calcination to obtain Al2 03 flakes and alkali salts in a molten salt, and (4) removal of the water soluble parts of the calcined molten salt obtained in step (3).

A positive electrode includes a lithium-based active material, a binder, a conductive filler, and discrete aluminum oxide nanomaterials. The aluminum oxide nanomaterials are mixed, as an additive, throughout the positive electrode with the lithium-based active material, the binder, and the conductive filler. The positive electrode with the discrete aluminum oxide nanomaterials may be incorporated into a lithium ion battery. The aluminum oxide nanomaterials may be formed by the following method. A solution is formed by mixing an aluminum oxide precursor and an acid. A carbon material is added to the solution, thereby forming an aqueous mixture having the carbon material therein. Hydrothermal synthesis is performed using the aqueous mixture, and precursor nanostructures are grown on the carbon material. The precursor nanostructures on the carbon material are annealed so that the carbon material is removed and aluminum oxide nanomaterials are formed.

A method for the production of aluminium hydroxide (Al(OH)3) is described wherein in a first tank a first aqueous solution of sodium aluminate (NaAl(OH)4) is provided and carbon dioxide (CO2) gas is added to the first tank to form a first aluminium hydroxide precipitate, and wherein a second tank containing a second aqueous solution of sodium aluminate is provided, wherein the sodium aluminate solution in the second tank is supersaturated and seed crystals are added to the second tank to form a second aluminium hydroxide precipitate. At least a fraction of the first aluminium hydroxide precipitate obtained from the first solution in the first tank is seeded into the second tank and/or at least a fraction of the second aluminium hydroxide precipitate obtained from the second solution in the second tank is seeded into the first tank.

A method for the production of aluminium hydroxide (Al(OH)3) is described wherein in a first tank a first aqueous solution of sodium aluminate (NaAl(OH)4) is provided and carbon dioxide (CO2) gas is added to the first tank to form a first aluminium hydroxide precipitate, and wherein a second tank containing a second aqueous solution of sodium aluminate is provided, wherein the sodium aluminate solution in the second tank is supersaturated and seed crystals are added to the second tank to form a second aluminium hydroxide precipitate. At least a fraction of the first aluminium hydroxide precipitate obtained from the first solution in the first tank is seeded into the second tank and/or at least a fraction of the second aluminium hydroxide precipitate obtained from the second solution in the second tank is seeded into the first tank.

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.

An object of the present invention is to provide an inorganic oxide powder suitable for forming an inorganic oxide porous membrane, which is superior in lithium ion conductivity and has insulation performance, on at least one surface of a positive electrode, a negative electrode and a separator which constitute a lithium ion secondary battery. The present invention relates to an inorganic oxide powder for use in forming an inorganic oxide porous membrane having insulation performance on at least one surface of a positive electrode, a negative electrode and a separator which constitute a lithium ion secondary battery, wherein the powder has 1) an oxide purity of 90% by weight or higher; 2) an average particle diameter of 1 m or less; and 3) an average three-dimensional particle unevenness of 3.0 or higher.

The present invention concerns a method of preparing aluminum monohydrate comprising the steps of i) mixing alumina feedstock with ethylenediamine tetraacetic acid, to obtain a feedstock mixture, and ii) subjecting the feedstock mixture to a hydrothermal treatment, wherein the wherein the pH of the feedstock mixture is at least 8. The resulting aluminum monohydrate, although starting from low purity feedstocks, shows an excellent purity and can be calcined to obtain high purity alpha alumina.

The present invention concerns a method of preparing aluminum monohydrate comprising the steps of i) mixing alumina feedstock with ethylenediamine tetraacetic acid, to obtain a feedstock mixture, and ii) subjecting the feedstock mixture to a hydrothermal treatment, wherein the wherein the pH of the feedstock mixture is at least 8. The resulting aluminum monohydrate, although starting from low purity feedstocks, shows an excellent purity and can be calcined to obtain high purity alpha alumina.