Abstract: Vanadium values are recovered from sulphur-containing cokes and ashes derived from heavy oils by a novel process comprising heating in the presence of alkali metal carbonate, contacting the resulting solid residue with water to form a leach and recovering the vanadium values dissolved therein. The heating step solubilizes only alkali metal vanadate and thus the leach solution is substantially free of contaminating substances.

Abstract: Hydrargillite is converted into boehmite by preparing a suspension (A) of hydrargillite in water with a proportion from 150 g/l to 700 g/l of dry material expressed as Al.sub.2 O.sub.3, subjecting it to heat treatment under pressure (D) at a temperature of from 200.degree. C. to 270.degree. C., the speed of the rise in temperature of said suspension being at least 1.degree. C./minute, and causing it to pass a period of time of from 1 minute to 60 minutes in a holding zone (D) at a temperature in the range of from 200.degree. C. to 270.degree. C.The boehmite produced has a granulometry which is at most identical to that of the initial hydrargillite, and has a much lower content of alkaline material.

Abstract: A process for preparing solid titanium trichloride useful for the polymerization of an .alpha.-olefin, which comprises precipitating violet-colored fine solid particles of titanium trichloride at a temperature of not higher than 150.degree. C. from a liquid of titanium trichloride liquefied in the presence of an ether, characterized in that after the amount of the precipitated violet-colored fine solid particles of titanium trichloride reaches at least 80% based on the total amount of titanium trichloride in the system, titanium tetrachloride is added in an amount within a molar ratio of from 0.2 to 10 based on the total amount of titanium trichloride in the system, followed by aging at a temperature of from 60.degree. to 120.degree. C.

Abstract: Tungsten can be extracted into solution from tungsten carbide powder residues with aqueous hydrogen peroxide to a greater extent by employing in solution a catalytic quantity of hydrochloric acid, such as a mole ratio to the tungsten preferably in the range of at least 0.1:1 moles of HCl per mole tungsten, and often up to about 2.5 moles of HCl per mole of tungsten at 55.degree. to 85.degree. C. The selection of the mole ratio in practice usually takes into account the grade of tungsten carbide starting material. It is very preferable to use at least 7 moles hydrogen peroxide per mole of tungsten and an extraction temperature of 65.degree. to 75.degree. C.

Abstract: Processes for the preparation of pure alumina powders or pure non-stoichiometric alumina-magnesia spinel powders starting with ammonium alum-based compositions which are dehydrated, the dehydration being carried out on dehydrated salts having a bulk density less than 0.2 kg/dm.sup.3 and wherein the dehydration is followed by a calcination with a heating schedule containing at least one intermediate stage at 750.degree. to 850.degree. C., the process of the invention permitting the reproducible production of such aluminas or spinels having specific surfaces of from 100 to 200 m.sup.2 /g and characterized by a very high homogeneity which guarantees a rigorously unimodal pore structure, such aluminas and spinels being useful in preparing isotopic enrichment barriers for gaseous diffusion, as well as metal polishes, catalysts, and catalyst supports.

Abstract: This invention relates to aluminium compounds and their preparation.In accordance with the invention a peptizable alumina hydrate is prepared by hydrolyzing an aluminium alkoxide at a water:aluminium ratio at or near the stoichiometric value. One example of an aluminium alkoxide which has been hydrolyzed in accordance with the present invention is aluminium sec-butoxide (Al(OC.sub.4 H.sub.9).sub.3.sup.s); thus alkoxide has been hydrolyzed at water:aluminium ratios of 3:1 and 4:1 to give peptizable alumina hydrates.Cold water (e.g. at 16.degree.-22.degree. C.) and aluminium alkoxide are preferably brought together to effect the hydrolysis.

Abstract: A process for the production of silicon nitride by reaction of silicon dioxide, carbon and nitrogen at temperatures above about 1300.degree. C. whereby a partial pressure of nitrogen above 1 bar is maintained during the reaction.

Abstract: A process for the production of alkali metal aluminum tetrahydrides from aluminum and alkali metal. The reactants, preferably in stoichiometric proportions, are pressure hydrogenated in an ether reaction medium in the presence of an aluminum-containing catalyst.

Abstract: This invention relates to a method for the production of anhydrous alumina having a desired .alpha.-conversion from alumina trihydrate.This method is directed to production of anhydrous alumina having a desired .alpha.-conversion from alumina trihydrate in which water is removed in a precalcining zone wherein the alumina trihydrate is heated to a temperature below 450.degree. C. Then, the precalcined dehydrated alumina is recrystallized to .alpha.-alumina in a reaction chamber by directing an oxygen containing gas to the reaction chamber, mixing and suspending the precalcined alumina and fuel in the oxygen containing gas and feeding the mixture to a combustion zone, followed by exothermal recrystallization of the alumina which is initiated by rapidly heating the precalcined alumina by burning the fuel in the oxygen containing gas in the hot combustion zone and withdrawing the recrystallized alumina from the top of the reaction chamber suspended in a combustion gas stream.

Abstract: A process for the production of alkali metal aluminum tetrahydrides from its elements by pressure hydrogenation, particularly characterized by production from an aluminum containing a reaction-promoting quantity of titanium, zirconium, hafnium, vanadium, niobium, or uranium. Titanium is preferred in a quantity of at least about 250 parts per part by weight aluminum. The process is preferably carried out on a semi-continuous basis in the presence of an alkali metal aluminate which is carried through to successive batches as an active heel.A novel composition of alkali metal aluminum tetrahydride in liquid reaction medium also containing alkali metal aluminate activator/catalyst. The alkali metal aluminate is preferably retained in a reaction heel for catalysis of subsequent reaction cycles.

Abstract: In a process for the production of alumina from aluminous raw material, an ammonoalunite intermediate is formed. The raw material is preferably a clay which is leached with sulfuric acid to form an aluminous solution which is separated from the solid materials. After any required extraction of iron, such as by liquid ion exchange, the solution is subjected to elevated temperatures and pressures in the presence of ammonium ions to form ammonoalunite which is recovered as a precipitate. The liquor is recycled to leach the clay, while the ammonoalunite is thermally decomposed to alumina. Gases liberated during decomposition are scrubbed with recycled liquor to form clay leach liquor. The alumina may be purified by washing with sulfuric acid to obtain a purity suitable for aluminum electrolysis.

Abstract: The disclosure relates to a process for separating gallium and indium from an aqueous solution by subjecting this latter to liquid/liquid extraction with the use of certain classes of organylphosphonic acid esters and separating the resulting liquid phases from one another.

Abstract: Processes are described for preparing pure ammonium molybdate from impure roasted molybdenum concentrates. An aqueous solution of nitric acid and ammonium nitrate is contacted with impure molybdenum concentrate to solubilize a major portion of the impurities. The resulting molybdenum concentrate is digested in ammonium hydroxide under conditions that maximize iron precipitation and removal. The resulting ammonium molybdate solution is separated from the sludge and further purified by chelating cation exchange resin in the ammonium form.

Abstract: A binder and a hardener therefor for a foundry aggregate. The binder is a resin obtained by reacting phosphoric acid with a mineral silicate. The hardener is a linear alkali metal polyphosphate, ammonium polyphosphate, a source of polyvalent cations, potassium olivine phosphate and other metal silico-phosphates or aluminum dihydrogen phosphate or mixtures there.

Abstract: A hydrogel binder for a foundry aggregate comprising, in combination, a metal silico-phosphate and as a hardener therefor a mixture of aluminum dihydrogen phosphate, water and phosphoric acid.

Abstract: Titanium and iron values are recovered from ores, concentrates and slags by effecting solid-state reduction and carburization to form titanium carbide and carburized iron, separation of the carburized iron, and low temperature chlorination of the titanium carbide to gaseous substantially pure titanium tetrachloride, which may be oxidized to pigmentary titanium dioxide.

Abstract: In a process is disclosed for recovering rhenium from tungsten and rhenium bearing material by oxidizing and fusing the starting material, solubilizing the tungsten and rhenium values, passing the resulting solution through a strongly basic anion exchange resin to retain the rhenium, removing the rhenium from the resin with an organic stripping liquid of tributylphosphate and hydrochloric acid, washing the remaining rhenium off the resin with water, combining the water and organic to form a two phase system in which the organic phase contains the major portion of the rhenium, and contacting with aqueous ammonia to strip values.

Abstract: This specification is directed to a method of making a compound selected from the group consisting of birnessite compounds of the formula Bi.sub.x Mn.sub.y O.sub.2y+1.5x.zH.sub.2 O, wherein the y/x ratio is in a range of from about 7 to about 18 and the z/y ratio is in a range of from about 0.5 to about 0.6, Pb.sub.x Mn.sub.y O.sub.2y+x.zH.sub.2 O, wherein the y/x ratio is in a range of from about 6 to about 10 and the z/y ratio is in a range of from about 0.5 to about 0.6, and manganese oxide compounds containing both of these compounds. The method is characterized by the following steps. A solution is formed by mixing Mn(NO.sub.3).sub.2 with a nitrate of bismuth or lead or mixtures thereof. The solution is maintained at a relatively constant temperature and NaOH is added to the solution, whereby Mn(OH).sub.2 and a hydroxide of bismuth or lead or mixtures thereof form a suspension. While the suspension is being agitated, oxygen is passed through the suspension, whereby the Mn(OH).sub.

Abstract: In the fluidized bed chlorination of oxidic materials, for example minerals such as bauxite, tantalite, columbite, wolframite or scheelite, the separation of metal values giving vaporous chlorides at the reaction temperature is enhanced by maintaining a zone substantially free of chlorine in the fluidized bed, for example a zone at least 0.25 m in depth measured from the expanded bed surface. A high aspect ratio bed and counter current movement of the bed matter and the chlorine within the bed are preferably used.

Abstract: A method of manufacturing metal titanate fine powder which is represented as MTiO.sub.3 wherein M is one of Ba, Sr and Ca is disclosed which includes the steps of preparing hydrolyzed compound of titanium compound and reacting the hydrolyzed compound of titanium compound with water soluble metal salt of one of Ba, Sr and Ca in an aqueous alkaline solution having pH not less than 13.