Abstract: There is described a method for the decomposition of aluminum nitrate crystals to alumina comprising the steps of:(a) melting the aluminum nitrate crystals;(b) evaporating from the melted crystals in a once through evaporator at the boiling temperature of the mixture and for a time sufficient to remove water and associated nitric acid and to provide a fluid having an alumina concentration of at least about 18% by weight;(c) decomposing the product of step (b) at a temperature of between about 150.degree. and about 200.degree. C. and recovering the heat of condensation of the resultant vapors;(d) further decomposing the product of step (c) in a fluidized bed decomposer at a temperature of between about 300.degree. and about 400.degree. C. to reduce the residual nitrate concentration in the product to between about 5 and about 10 weight percent;(e) decomposing the product of step (d) in a fluidized bed decomposer at a temperature of between about 500.degree. and about 800.degree. C.

Abstract: Alumina having a low loose bulk density is obtained by hydrolyzing aluminum alkoxides with water in the presence of lithium hydroxide or lithium salts yielding lithium ions. The amount of density reduction is proportional to the amount of lithium ion present.

Abstract: A highly porous alumina having a large surface area and a low bulk density is prepared by hydrolyzing an aluminum alcoholate at a temperature of 40.degree. to 90.degree. C. in an aqueous solution containing 8 to 30% by weight of a compound which upon drying or activating splits out NH.sub.3 and/or CO.sub.2, there being used 0.5 to 3 parts by weight of the compound per 10 parts of aluminum alcoholate. The aluminum oxyhydrate paste formed by the hydrolysis is separated from the alcohol phase, in a given case is also purified, and subsequently dried or activated.

Abstract: The method of preparing granulated activated alumina consists in that alumina trihydrate is decomposed by bringing it in contact with a bed of a solid heat carrier having the temperature of 350.degree. to 600.degree. C., the contact time being from 0.05 to 0.5 second, to obtain a product of decomposition in the form of amorphous aluminium hydroxide. Said decomposition product is mixed with water into a suspension having the concentration of 100-500 g/liter, calculating with reference to aluminium oxide, and hydrated at a temperature of 20.degree.-100.degree. C. and the pH of 5 to 12 for 0.5 to 10 hours. The hydrated decomposition product is then treated with an acid, that can form water-soluble basic salts of aluminium, at a temperature of 20.degree. to 150.degree. C., granulated, dried at a temperature of 20.degree. to 150.degree. C., and calcined at a temperature of 400.degree. to 600.degree. C.

Abstract: Alumina agglomerates with high mechanical strength and selectable particle size are obtained by compacting an intermediate product resulting from incomplete decomposition of a substance of the group comprising hexahydrated aluminum chloride, hydrated aluminum nitrate, hydrated aluminum sulfate of the formula Al.sub.2 O.sub.3, xSO.sub.3, yH.sub.2 O and hydrated aluminum sulfite of the formula Al.sub.2 O.sub.3, xSO.sub.2, yH.sub.2 O, which after thermal decomposition contain from 0.5 to 15% by weight of Cl, of nitrogen oxide expressed as N.sub.2 O.sub.5 or of sulfur expressed as SO.sub.3 or SO.sub.2, which compacted product is then granulated and the granulated product subjected to heat treatment.

Abstract: Pure alumina is produced from aluminum metal by steps of activation by stripping the oxide layer in an acidic aqueous medium; washing in a neutral medium; reacting in a neutral, acidic or alkaline medium to give hydrated alumina; and igniting the hydrated alumina.

Abstract: Disclosed is a method for forming shaped catalysts from a rehydratable alumina composition. The method includes a staged rehydration procedure to stabilize the rehydratable alumina to facilitate extrusion processing.

Abstract: Substantially spherical alumina particles are obtained by a process comprising ageing substantially spherical alumina hydrogel particles obtained by the oil-drop method in an ammonium hydroxide solution wherein the concentration of ammonia changes continuously from an initial concentration in the range of from about 0.05 wt.% to about 0.5 wt.% to a final concentration in the range of from about 0.8 wt.% to about 2.5 wt.%. Alumina particles obtained by this process possess improved physical strength. Alumina particles which are obtained by calcining alumina particles aged in an ammonium hydroxide solution, wherein the concentration of ammonia increases continuously, at a temperature in the range of from 650.degree. to 800.degree. C in an atmosphere containing 30 mol.% or more of H.sub.2 O possesses a further improved thermal stability.

Abstract: Alumina catalyst carriers are produced by bonding pre-fired gibbsite with microcrystalline boehmite. Superior strength of the product is achieved by use of gibbsite fired to an L.O.I. at 1000.degree. C of 8% or less, or preferably less than 4%.

Abstract: An alumina composition particularly useful as a catalyst support or carrier material is disclosed. The alumina is characterized by a method of preparation which comprises admixing an alpha-alumina monohydrate with an alkaline solution having a pH of at least about 7.5 and forming a stable suspension. A salt of a strong acid is commingled with the suspension to form a paste or dough which is subsequently formed into extrudates, and dried and calcined.

Abstract: Alumina monohydrate is produced by leaching calcined clay and subjecting the leach liquor to pressure hydrolysis wherein the vapor and heat resulting from the pressure hydrolysis are directly utilized for leaching of the calcined clay. The aluminum monohydrate may be roasted to yield alumina.

Abstract: Aluminum carbonate hydroxide ammonium, a new compound, is produced by causing a solution of ammonium hydrogencarbonate to be reacted upon by a soluble aluminum salt. .alpha.-Alumina is obtained by thermal decomposition of this ammonium aluminum carbonate hydroxide. By sintering said .alpha.-alumina, there is obtained sintered .alpha.-alumina.

Abstract: Formed products are made from aqueous aluminum oxyhydrate by peptizing the aqueous aluminum oxyhydrate with an acid and then subsequently adding a dilute solution of ammonia or an ammonia yielding compound following by extrusion, drying and calcining.

Abstract: Alumina monohydrate is produced by treating aluminum nitrate solution at a temperature of about 250.degree. to 350.degree. C and a pressure of about 500 to 2500 psig.

Abstract: A high surface area alumina is provided exhibiting a surface area ranging from about 350 to about 550 meters.sup.2 /gram.The high surface area alumina is prepared by reacting substantially anhydrous aluminum chloride with ammonia at temperatures ranging from about 100.degree. to about 900.degree. F. to form an aluminum chloride-ammonia complex comprising aluminum chloride polyammoniates, and hydrolyzing said polyammoniates to obtain high surface area alumina.

Abstract: Water dispersible aluminum hydroxide is prepared by treating an acid dispersible aluminum hydroxide with 1 to 9 weight % of a gaseous acid.

Abstract: Method of agglomerating solids in a liquid suspension utilizing in the bridging liquid an additive chemically active with respect to such solids. The solid to be agglomerated is suspended in a first liquid which is, or is made to be, at least relatively nonwetting with respect thereto. A second immiscible or bridging liquid is then introduced into said first liquid. Said second liquid is, or contains dissolved therein material which is, reactive to such solid material. The entire system is then agitated and the solid material thereby formed into agglomerates. The use of a chemically reactive material in the bridging liquid provides a wide range of selectability of and control over the properties, either physical or chemical, of the resulting agglomerates.

Abstract: Modification of the pore volume distribution of an alumina base catalyst support is accomplished by treating an alumina precursor of chi-rho-eta structure with an aqueous ammonium carbonate or bicarbonate solution under pressure at about 100.degree.-160.degree. C for 10-24 hours, followed by drying and thermal activation at a temperature of at least about 500.degree. C. The resulting support will possess more than about 70% of its total pore volume in the 45-300 angstrom unit pore diameter range. This pore volume distribution renders it particularly suitable for use as a catalyst carrier for hydrodesulfurization purposes.

Abstract: Pure, high surface area alumina is produced by the reaction of aluminum salts with lower aliphatic epoxides in an aqueous media and is washed with aqueous solutions of ammonia which have a pH of at least 7.

Abstract: A method of preparing spheroidal refractory inorganic oxide particles characterized by low bulk density in combination with high micropore volume is disclosed. The particles, especially low bulk density - high micropore volume alumina particles, are useful as a support or carrier material for catalytically active materials to yield an improved hydrocarbon conversion catalyst.

Abstract: A process for preparing aluminium oxide beads from alumina hydrogel, which comprises polymerizing, in a hot and substantially water-immiscible fluid, an aqueous mixture comprising alumina hydrogel and alumina hydrosol and a water-soluble monomer whose uncross-linked polymer is water-soluble or forms a gel, this mixture being dispersed as droplets into a hot fluid in which substantial polymerization of the monomer occurs.

Abstract: A process for preparing aluminum oxide beads from alumina hydrogel, comprising polymerizing in a hot and substantially water-immiscible fluid, an aqueous mixture which contains alumina hydrogel and a water soluble monomer whose uncross-linked polymer is water soluble or forms a gel, this mixture being dispersed as droplets into said fluid in which substantial polymerization of said monomer is performed.

Abstract: Dispersible colloidal particles of .alpha. alumina monohydrate are prepared by conditioning aqueous solutions of an aluminum salt with an organic solvent and the precipitating alumina with an aqueous solution of base. The reaction mixture is heated under pressure, filtered, washed and dried to obtain the product.

Abstract: Alumina fibre is prepared by spinning a solution containing an aluminium compound and an organic polymer, removing solvent and contacting the fibre with ammonia or an amine before conversion of the fibre to alumina.

Abstract: A method of manufacturing high surface area spheroidal alumina particles. A finely divided eta alumina is admixed and suspended in an alumina hydrosol and the mixture thereafter converted to spheroidal particles comprising eta and gamma alumina by the oil-drop method. The alumina spheres are particularly useful as a high surface area support or carrier material for catalytic components, and as a high surface area adsorbent.