Abstract: The present invention relates to a method for recycling iron and aluminum in a nickel-cobalt-manganese solution. The method comprises the following steps: leaching a battery powder and removing copper therefrom to obtain a copper-removed solution, and adjusting the pH value in stages to remove iron and aluminum, so as to obtain a goethite slag and an iron-aluminum slag separately; mixing the iron-aluminum slag with an alkali liquor, and heating and stirring same to obtain an aluminum-containing solution and alkaline slag; and heating and stirring the aluminum-containing solution, introducing carbon dioxide thereto and controlling the pH value to obtain aluminum hydroxide and an aluminum-removed solution.

Abstract: A method of removing impurities from silicates or clays through selective flocculation. The method comprises mixing a chemical product with silicates or clays, where the chemical product comprises a copolymer of acrylic acid, acrylamide, or a combination of acrylic acid and acrylamide with at least one of the following monomers: hydroxyl ethyl methacrylate, 2-acrylamido-2-methyl propane sulfonic acid, and/or 3-allyloxy-1,2-propanediol, or a derivative thereof; allowing impurities to separate from the silicates or clays; and removing the impurities from the silicates or clays. The chemical product may further comprise tannic acid, where the active tannic acid to active polymer concentration is 1% to 25% tannic acid, or more particularly 1% to 5% tannic acid.

Abstract: A process for preparing a catalytic cracking catalyst, which process comprises: a molecular sieve is introduced into a gas-phase ultra-stabilization reactor, the molecular sieve is moved without the conveying of carrier gas from a molecular sieve inlet of the gas-phase ultra-stabilization reactor to a molecular sieve outlet of the gas-phase ultra-stabilization reactor, and the molecular sieve is contacted and reacted with a gaseous SiCl4 in the gas-phase ultra-stabilization reactor, the molecular sieve resulting from the contacting and the reacting is optionally washed, then mixed with a matrix and water into slurry, and shaped into particles.

Abstract: The invention provides methods and compositions for the addition of a CGM to precipitation liquor of a Bayer process. The CGM comprises a neopolyol, an ester derived from a neopolyol, and/or an ether derived from a neopolyol. Optionally the CGM may comprise water and/or an antifoaming agent and/or a hydrocarbon carrier liquid. The CGM is quite effective and results in a significant increase in mean particle size of produced alumina crystals.

Abstract: Non-spherical siliceous particles having a plurality of porous branches are disclosed and claimed. The porous branches are randomly oriented and elongated, ring-like, and/or aggregated. An additive introduced during synthesis of the particles modifies pore volume and morphology. The tunability of the pore volume includes an inner diameter ranging from about 2 ? to about 50,000 ?. Synthesizing the particles includes mixing under constant or intermittent stirring in a reaction vessel an aqueous silicic acid solution with an acidic heel solution to form a mixture. The stirring may optionally be performed at a variable speed. An additive is introduced into the mixture at a controlled rate, wherein the additive imposes a pH change from a lower pH to a higher pH to the mixture to induce siliceous particle precipitation.

Abstract: As population density increases, the transportation of hazardous chemicals, including acids and disinfectants, lead to an increased incidence of spills while the consequences of spills become more serious. While solutions of halide acids, hypohalites and halites are safer disinfectants for transportation, handling, storage and use than traditional gaseous chlorine, the manufacturing cost of these disinfectants has here-to-fore limited their use. Economical processes are presented for the manufacture of O2, halogen oxides, halide acids, hypohalites, and halates; as well as polynucleate metal compounds, metal hydroxides and calcium sulfate hydrate (gypsum). The instant invention presents methods and processes that incorporate the use of sulfur. This is while environmental regulators, such as the US EPA, require an increased removal of sulfur from hydrocarbon fuels, thereby creating an abundance of sulfur, such that the refining industry is in need of a way to dispose of said abundance of sulfur.

Abstract: Disclosed is a method of manufacturing a metal oxide nano powder comprising preparing a first dispersed solution by adding a nano-sized metal powder to water and dispersing the metal powder within the water, performing a hydration reaction of the first dispersed solution at a temperature of about 30 to about 70° C. to generate a precipitation, and filtering and drying the precipitation to prepare a metal oxide powder. Also, disclosed is a metal oxide nano powder manufactured by the method described above, and having any one of a bar-form, a cube-form, and a fiber-form.

Abstract: A process for the production of alumina trihydrate by alkaline digestion of bauxite using the Bayer process in which aluminate liquor and insoluble residues are separated using a solid/liquid separation device (E; W2; DC) characterised in that the said slurry (21a; 41; 230?) is at least partially passed through a hydrocyclone (H1; H21; H22; H3) to improve and accelerate the separation of the sodium aluminate liquor from the insoluble residues in the slurry (21a; 41; 230?) containing the said liquor and the said residues and that supplies or is derived from the said liquid-solid separation device. In a first embodiment, at least one hydrocyclone is used at the upstream side of the settler-thickener, as clarifier of the pregnant liquor. In a second embodiment, at least one hydrocyclone is used as a thickener of insoluble residue mud. In a third embodiment, a hydrocyclone is used in combination with the causticisation settler.

Abstract: A Bayer liquor is produced by dissolving bauxite in hot caustic soda. The liquor is cooled so that it is supersaturated, and seed crystals of gibbsite are added to the liquor (16). At the same time at least part of the liquor is subjected to intense ultrasonic irradiation (34) such as to cause cavitation, preferably by passing liquor and seed crystals (28) through a recirculation duct (30). The ultrasound increases the proportion of fines by breaking up any crystal agglomerates and also by generating crystal nuclei, and also removes fouling from crystal surfaces. The precipitation process is consequently more effective. If ultrasound is applied when measurements indicate that there are insufficient fines in the liquor, this improves the consistency of the precipitation process.

Abstract: The present invention relates ways to increase the output of a high quality product from the aluminum hydroxide recovery processes such as the Bayer process. The invention is a method of increasing the size of precipitated aluminum hydroxide while not reducing the total production amounts. The invention relates to the use of a crystal growth modifier compositions added to the precipitation liquor to increase the particle size distribution of the precipitated alumina trihydrate.

Abstract: A process for the removal and causticisation of sodium oxalate and/or sodium sulphate from a Bayer process liquor containing sodium carbonate and one or both of sodium oxalate and sodium sulphate in an alumina refinery is described. The process is based on the observation that to efficiently causticise sodium oxalate solutions, it is first necessary to remove the aluminate ion from solution, optionally with recovery of the aluminate ion in some later step. This is effected by removing aluminate ions from the Bayer liquor through the formation of a carbonate bearing hydrocalumite and/or sulpha-bearing hydrocalumite. The liquor may then be treated with sufficient lime to remove and causticise any residual carbonate ions and some or all of the oxalate ions present so that any reacted lime solids thus formed can be separated and safely disposed of.

Abstract: A process for the removal and causticisation of sodium oxalate and/or sodium sulphate from a Bayer process liquor containing sodium carbonate and one or both of sodium oxalate and sodium sulphate in an alumina refinery is described. The process is based on the observation that to efficiently causticise sodium oxalate solutions, it is first necessary to remove the aluminate ion from solution, optionally with recovery of the aluminate ion in some later step. This is effected by removing aluminate ions from the Bayer liquor through the formation of a carbonate-bearing hydrocalumite and/or sulphate-hearing hydrocalumite. The liquor may then be treated with sufficient lime to remove and causticise any residual carbonate ions and some or all of the oxalate ions present so that any reacted lime solids thus formed can be separated and safely disposed of.

Abstract: A process is disclosed for the treatment of an alumina process feedstock prior to transferring the treated feedstock to an alumina process for extracting refined alumina from the treated feedstock. The treatment process includes the following steps: (a) heating the alumina process feedstock to a temperature of 400C. to 650C. by direct contact with combustion gases, and (b) cooling the heated feedstock to a temperature at which it can be handled and fed to the alumina process. The treatment process is characterised by controlling the contact time of the solid alumina process feedstock at temperatures in the above range in step (a) to less than 5 minutes.

Abstract: A process is provided for the treatment of an alumina process feedstock prior to transferring the treated feedstock to an alumina process for extracting refined alumina from the treated feedstock. The treatment process includes: (a) heating the alumina process feedstock to a temperature of 400° C. to 650° C. by direct contact with combustion gas, and (b) cooling the heated feedstock to a temperature at which it can be handled and fed to the alumina process. The treatment process also includes controlling the contact time of the alumina process feedstock at temperatures in step (a) to ensure decomposition of alumina trihydrate and alumina monohydrate. The process also includes: (i) limiting the maximum temperature of incoming gas to a stage of the process in which the alumina process feedstock reaches the above temperature range of 400° C. to 650° C.

Abstract: A process in which material comprising an aqueous liquid with dispersed particulate solids is pumped as a fluid then allowed to stand and rigidify and the rigidification is improved whilst retaining the pumpability of the material by combining polymeric particles with the material during or prior to pumping the material, wherein the polymeric particles comprise water soluble polymer which has an intrinsic viscosity of at least 3 dl/g. The process of the invention more effectively minimises the area taken up by a stack of the material of given volume whilst maintaining the pumpability of the material. This invention is particularly suited to material that comprises red mud from the Bayer alumina process.

Abstract: An improvement in the Bayer process for producing alumina trihydrate in which bauxite ore is digested in a mixture with a digestion sodium aluminate liquor to produce a slurry, the slurry is settled to remove undigested residues therefrom and produce a pregnant liquor of sodium aluminate and alumina trihydrate is precipitated from the pregnant liquor in the presence of alumina trihydrate recycled as seed. When beginning the precipitation, an aliquot of the pregnant liquor with recycled alumina trihydrate is removed, subjected to mechanical action of an intensity and for a time sufficient to cause formation of seeds, and returned with the formed seeds to the beginning of the precipitation.

Abstract: The recovery of aluminum chloride from deactivated alkylation catalyst complexes by hydrogenation using hydrogen gas and an aluminum catalyst is disclosed. Using aluminum to catalyze the hydrogenation allows the reaction to proceed at a lower temperature and pressure while reducing the amount of hydrogen chloride present in the reactor thus reducing the corrosiveness and cost of the aluminum chloride recovery. Methods for batch, batchwise continuous, and continuous aluminum chloride recovery are disclosed.

Abstract: A process for preparing an ultra-white alumina trihydrate having a G.E. brightness of at least about 98%. The product is alumina trihydrate that has been rehydrated with coprecipitation, and the crystal phase of the product is primarily gibbsite in thin platelet form having a ratio of thickness to diameter of about 0.2 to about 0.3. The product is prepared by flash activation of a white initial alumina trihydrate, addition of the activated material to a purified sodium aluminate liquor having an alumina to caustic ratio of about 0.5, and rehydrating and precipitating the alumina at ambient temperature under agitation for about 48 hours, followed by washing and drying of the resulting precipitate. The material is especially useful as a filler or coating in papermaking, and it can be substituted for a portion of titanium dioxide pigment in the ratio of 1:1, and can be combined with titanium dioxide as a pigment mixture, either in slurry form or in dry form.

Abstract: A stable aqueous sol of amorphous alumina containing Al.sub.2 O.sub.3 up to 15% by weight and 0.1 to 0.5 gram equivalent of an anion of acid to 1 mol of aluminum in the sol, in which the colloidal particles of amorphous alumina have a controlled thickness in a range of 20 to 100 millimicrons and a uniform length in a range of 200 to 500 millimicrons is produced by a process comprising feeding an aqueous solution of an acid into an aqueous slurry containing 1 to 7% by weight of metallic aluminum, 10 to 200 ppm by weight as Si0.sub.2 of a water-soluble silicate and 0 to 20 ppm by weight of a water-soluble sulfate as S0.sub.4 to the water in the slurry while maintaining the slurry at a temperature of 80.degree. C. to boiling point under normal pressure, said acid being in an amount of 0.1 to 0.5 gram equivalent to 1 mol of the metallic aluminum in said slurry, at a rate of 0.001 to 0.

Abstract: The disclosure describes an apparatus for performing at least two successive chemical reactions in the same container. In order to successively carry out several chemical reactions in the same container (10), e.g. dosing uranium in the presence of plutonium and fission products, the container is placed in a working station above which issue tubes (16, 20) for supplying the products necessary for the reactions. When a product has to be introduced, a computer controls the descent of the corresponding tube. When the product may react inopportunely if it drops into the container (10) outside the time intended for this purpose, the lower end of the product supply tube (16) is automatically laterally displaced with respect to the container, when the tube is in the top position, e.g. by the cooperation of a pawl (102) with a slot (100) forming a cam.

Abstract: Process for the production of a short-prismatic aluminum hydroxide by decomposing a supersaturated sodium aluminate liquor. The product can be used as a pigment and filler in the paper industry, as a flame-retardant filler in plastics and as a white pigment in paints and enamels.

Abstract: An improvement in the process for extracting alumina from gibbsitic bauxites, wherein the basic, known process comprises mixing the bauxites with a sodium hydroxide-sodium aluminate digestion liquor, digesting the bauxites at a temperature in the range of 100.degree.-180.degree. C., diluting the resulting slurry, separating the red mud therefrom, precipitating alumina hydrate by cooling and agitation of the sodium aluminate liquor, and calcining the alumina hydrate precipitate to obtain alumina, wherein the improvement is characterized by so controlling the process that, in the liquid phase of the slurry leaving the digestion reactor, the reactive hydroxide ion concentration is maintained below 6 g/l, and preferably between 0 and 2 g/l, where the reactive hydroxide ion concentration is defined by the following formula: ##EQU1## where: C.sub.Al.sbsb.2 O.sub.3,gi.sup.eq is the equilibrium solubility of Al.sub.2 O.sub.3 for gibbsite, in g/l.C.sub.Al.sbsb.2 O.sub.3 is the actual concentration of Al.sub.2 O.sub.

Abstract: A method is described for mixing a difficult to wet, finely divided powder, e.g. alumina dust, with an aqueous liquid, e.g. Bayer process spent liquor. In the method, the liquor is introduced into a cylindrical mixing zone having a conical bottom zone, the liquor being continuously introduced into the mixing zone as a high velocity stream tangentially immediately above the conical zone to thereby form a rapidly moving vortex within the mixing zone. The dust is caused to fall into the center of the vortex whereby the dust is rapidly engulfed by the liquor with little or no dusting. The thus formed slurry is continuously removed from the bottom of the conical zone and may be processed through a classification circuit, to be separated as fine seed and returned to the precipitation circuit where the fine particles are agglomerated and grown to larger particles of alumina by contact with Bayer process pregnant liquor.

Abstract: The present invention provides a process for the production of fine, tabular boehmite crystals substantially within the size range of 0.2-0.8 microns. The crystals are particularly suitable for use as a pigment/filler in paper, paint and ink applications.

Abstract: Transparent conductive coatings excellent in transparency are provided on substrates such as glass, plastics, etc. by the use of conductive coating materials obtained by maintaining aqueous solutions of hydrolyzable tin containing or indium containing compounds at pH of 8-12, and gradually hydrolyzing said compounds in the solutions to form sols containing colloidal particles, followed by drying and calcining.

Abstract: Process for the production of hydrated aluminae through the precipitation of aluminum hydroxide in a reactor by the reaction of an aluminum compound soluble in a polar solvent with a precipitating agent, also solubilized in the polar solvent, in constant conditions of pH, temperature, concentration and agitation; concentration of the suspension of precipitated aluminum hydroxide; crystallization in an alkaline pH, essentially constant; separation of the crystallized aluminum hydroxide, for later washing and drying. The product obtained is homogeneous and with excellent characteristics for utilization in the manufacturing of catalysts and catalytic supports. The process can be applied, advantageously, in the treatment of the acid waste from processes which utilize Friedel-Crafts type reactions, obtaining, in addition to the hydrated alumina, a liquid effluent with low metal contents.

Abstract: A process for the production of pure aluminum trihydroxide having a controlled median diameter of less than 4 microns with a unimodal distribution and a minimum deviation. The process comprises contacting, for a short time, sodium aluminate solution with a small quantity of ground aluminum trihydroxide having a specific BET surface area of at least 8 m.sup.2 /g, separating the sodium aluminate solution from the solid phase comprising ground aluminum trihydroxide and aluminum trihydroxide precipitate containing impurities, then decomposing the purified sodium aluminate solution in the presence of a quantity of pure ground aluminum trihydroxide from a preceding decomposition operation to precipitate a very pure aluminum trihydroxide having the specified median diameter.

Abstract: The invention concerns a process for the precipitation of aluminium hydroxide by seeding in two phases, which is intended to produce at a high level of productivity alumina with large grains, referred to as `sandy coarse`, by precipitation in a succession of tanks in cascade relationship of a supersaturated solution of sodium aluminate coming from alkaline attack on bauxite in accordance with the BAYER process. The process comprises three stages:in the first agglomeration stage, the supersaturated aluminate liquor is introduce into the tank, with an equivalent amount of terms of Na.sub.2 O of between 110 and 175 g/liter, at a temperature of between 65.degree. and 80.degree. C.

Abstract: A process for the production of aluminum trihydroxide having a controlled median diameter of less than 4 microns, with a unimodal distribution and minimum deviation. The process comprises grinding aluminum trihydroxide until the aluminum trihydroxide has a specific BET surface area of at least 8 m.sup.2 /g, adding the ground aluminum trihydroxide to a sodium aluminate solution, and then decomposing the solution to precipitate aluminum trihydroxide having the required median diameter.

Abstract: The present invention relates to the production of alumina and, more specifically, to a process for desilication of aluminate solutions.The process of desilication according to the present invention comprises treatment of the aluminate solution first with a calcium-containing reagent "a" which is a product of the reaction of desilication of the aluminate solution; reagent "a" contains mainly calcium hydrogarnet of the formula:3CaO.Al.sub.2 O.sub.3.nSiO.sub.2 (6-2n)H.sub.2 Owherein n.ltoreq.1, and then with a reagent "b" of the formula:4CaO.Al.sub.2 O.sub.3 (0.1-0.6)X.mH.sub.2 Owherein X is CO.sub.2 and/or SO.sub.3 ; m=8 to 15. The treatment of the aluminate solution with reagent "a" is carried out for 0.5 to 2 hours at a temperature ranging from 40.degree. to 105.degree. C. Weight ratio of reagents "a" and "b" is maintained within the range of from 1:1 to 3:1.The process according to the present invention is useful in the manufacture of alumina.

Abstract: A precipitation system is provided for the production of strong, coarse alumina hydrate (Al.sub.2 O.sub.3.3H.sub.2 O) from Bayer process aluminate liquors. In the system three distinct, but interconnected processing stages are utilized which comprise an agglomeration stage, a growth stage and a seed generation stage. In the agglomeration stage hydrate particles agglomerate to form coarse particles; in the growth stage these particles grow and acquire strength; while in the seed generation stage alumina hydrate seed is generated to be used in the agglomeration and growth stages.The precipitation system combines the advantages of both the American and European Bayer processes in that it results in the production of a strong, coarse product hydrate and an increased yield.

Abstract: A process for the removal of aluminum chloride from a liquid solution thereof with the liquid metal chlorides resulting from the chlorination of titaniferous materials by mixing water and sodium chloride with the liquid solution in amounts such that the amount of water is less than equimolar with respect to the total amount of aluminum chloride and the combined amount of water and sodium chloride is at least equimolar with respect to the total amount of aluminum chloride. This process significantly decreases the corrosion of apparatus associated with the presence of aluminum chloride and substantially eliminates losses of titanium tetrachloride and ferric chloride present in the liquid solution and reduces the formation of HCl.

Abstract: Nickel values contained in oxidic ores are recovered by leaching with sulfuric acid. The ore is slurried with water, preheated to a leaching temperature between about 230.degree. C and about 300.degree. C and the preheated slurry is fed to one or more vigorously agitated autoclaves, operating continuously in series. Sulfuric acid is added incrementally to the preheated slurry to minimize the amount of iron and aluminum in solution until between about 0.15 part and about 0.8 part of acid per part of dry ore is added to the slurry, thereby minimizing the deposition of scale in the autoclaves.

Abstract: The leaching efficiency of nickeliferous lateritic ore is optimized by scalping the ore to remove a coarse low-nickel fraction and provide a fine nickel-rich fraction which is then high pressure leached in a sulfuric acid solution by controlling the parameters temperature, pulp density, the rate of acid addition, leaching time, agitation rate, etc., whereby a pregnant solution is obtained with the nickel to (Fe+Al+Cr) ratio exceeding about 2.