Abstract: Zirconium dioxide which is monoclinic to at least 80% by weight and has a BET surface area of at least 100 m.sup.2 /g is prepared by admixing aqueous zirconium salt solutions with ammonia, drying and calcining the precipitation product, aging the precipitation product, prior to drying, in aqueous phase at from 0 to 300.degree. C. and carrying out the calcination at from 200 to 600.degree. C.

Abstract: An nickel hydroxide positive electrode active material which can be made by an ultrasonic precipitation method. The nickel hydroxide active material is characterized by the composition: ##EQU1## where x, the number of water ligands surrounding each Ni cation, is between 0.05 and 0.4 and y is the charge on the anions.

Abstract: A process is provided for disposing of hydrogen sulfide contained in a gas stream, wherein a first gas feed stream having a hydrogen sulfide gas component, a second gas feed stream having an oxygen gas component, and an aqueous liquid feed stream are combined to form a reaction mixture. The aqueous liquid feed stream may be water available in remote oilfield locales, such as produced water, or sea water. The aqueous liquid feed stream may include a significant concentration of preexisting sulfate ions, in which case it is generally desirable to remove the preexisting sulfate ions using membrane separation before mixing the aqueous liquid feed stream with the first and second gas feed streams. The resultant low sulfate liquid may further comprise one or more of the following dissolved ions: Na.sup.+,K.sup.+, Mg.sup.2+, Cl.sup.-, Br.sup.-, HCO.sub.3.sup.-.

Abstract: An installation and a method are described for the treatment of a gas containing hydrogen sulphide, the gas (1) being washed in a first gas scrubber (5) with an alkaline wash liquid and the spent wash liquid (4) being treated in an aerobic reactor (6) with oxygen in the presence of sulphide-oxidising bacteria and the effluent (9) from the aerobic reactor (6) being re-used as wash liquid (3) and the elementary sulphur formed during the treatment with oxygen being removed from the effluent (19), the effluent (13) from which sulphur has been removed being treated in an anaerobic reactor (17) with sulphate-reducing bacteria and returned to the aerobic reactor (6). The installation and the method can also be used for simultaneous removal of SO.sub.2, COS, CS.sub.2, NH.sub.3 and HCN.

Abstract: A method of solvent extraction of a nickel sulfate solution uses a multi-stage, counter-current, organic solvent extraction system composed of at least two extractors connected in series, and includes a first extraction step of feeding a crude nickel sulfate solution that contains sodium and ammonium impurities into a second-stage extractor, wherein it is treated in countercurrent flow and at a pH of 6.5 to 7.0 with an organic extractant fed into the second-stage extractor from the first-stage extractor, to thereby extract some of nickel in the crude nickel sulfate solution into the organic extractant; and a second extraction step of transferring the nickel-containing, organic phase to an organic phase-scrubbing step to remove sodium and ammonium, while transferring the nickel sulfate solution, from the first extraction step and from which some of nickel has been removed, to the first-stage extractor, wherein it is treated in countercurrent flow and at a pH of 5.5 to 6.

Abstract: Amorphous sodium silicate-metal sulfate composite powder having water softening power and having small hygroscopicity, and useful as a detergent builder is provided. This amorphous sodium silicate-metal sulfate composite powder is characterized in that it contains a metal sulfate, for example, sodium sulfate, as solid solution, and when the SiO.sub.2 /Na.sub.2 O molar ratio is expressed by n and the specific surface area thereof is expressed by S (m.sup.2 /g), n and S satisfy the following expressions:1.60.ltoreq.n.ltoreq.2.800.10.ltoreq.S.ltoreq.2.00, provided that it is assumed that the molar number of Na.sub.2 O is the molar number of Na.sub.2 O based on sodium silicate, and does not contain the molar number of Na.sub.2 O based on sodium sulfate in the case where the metal sulfate is sodium sulfate. This powder is prepared by grinding sodium silicate cullet containing the metal sulfate as solid solution.

Abstract: Heavy metal values can be removed and separated from a substance having a suitable amount of the heavy metal values by contacting the substance with a fluid containing sulfur trioxide to prepare a corresponding heavy metal sulfate, which is followed by leaching the sulfate therefrom and separating the leached sulfate. For example, mercury metal, oxide or sulfide, or methyl mercury, such as can be found in used fluorescent lamps and household batteries, in industrial flue sands, fly ash, contaminated soils, etc., can be removed by contact of crushed lamps or batteries, samples of the flue sands, fly ash, or contaminated soils, etc., with a mixture of sulfur trioxide in air to form mercuric sulfate, which is leached with a suitable leaching agent such as water, aqueous hydrochloric acid, hot dilute sulfuric acid, or concentrated sodium chloride solution, and sequestered by use of an ion exchange resin or precipitated as sulfides for further isolation of mercury value.

Abstract: Process for using reactions of gas/solid type in which the solid reactant contains an at least partially hydrated salt.The process makes it possible to shift the position of the equilibrium line of the reaction under consideration and to reduce its slope in a Clapeyron diagram so as to cover a wider temperature region for a limited pressure range.

Abstract: Sulfur oxides are removed from a gas containing same by contacting the gas with a system including ammonium, potassium, and/or sodium salts in a solid phase and ammonium, sodium, and/or potassium hydrogen sulfate in a liquid phase. The sulfur oxides react with the solid phase to form a hydrogen sulfate in a liquid phase. The hydrogen sulfate is regenerated and returned to the reaction zone as a sulfate. Sulfuric acid may be produced as a byproduct. Ammonia injection into the gas stream which optionally contains nitrogen oxides, converts the nitrogen oxides into nitrogen. The excess ammonia reacts with the sulfur oxides to precipitates in the sulfur oxides reaction zone.

Abstract: A manufactured stannous sulfate granulate is suitable for electrolytically coloring anodized aluminum with metallic salts, where the granulate particles have a linear extension from 0.1 to 10 mm. Also disclosed are a process for manufacturing the same and using it for electrolytically coloring anodized aluminum with metallic salts. The manufactured stannous sulfate granulate is characterized by technical advantages, such as storage stability, easy dispensibility, and absence of dust, compared to conventionally used stannous sulfate powders.

Abstract: A cosmetic assembly includes a stick of alum (1) deodorant, that is formed with a transverse passage (3) in which is placed a fixing pin made of an elastic material, and a casing in which the stick is placed. The fixing pin (4) is adapted to engage the inside wall of the casing (2) so as to fix the stick of alum within the casing by friction. The cosmetic assembly of the present invention enables sticks of alum of varying sizes to be used with standard type casings.

Abstract: Disclosed is an improvement on a process in which sodium chromate is reacted with sulfuric acid to produce sodium bichromate and sodium sulfate, and the sodium bichromate is reacted with sulfuric acid to produce chromic acid and sodium bisulfate. In the improvement, the sodium sulfate and sodium bisulfate are reacted with hydrogen chloride to produce sulfuric acid, which is recycled, and sodium chloride.

Abstract: Tri- and tetravalent vanadium solutions suitable for a redox battery are produced as follows. Vanadium pentaoxide or ammonium vanadium is reduced in the presence of a concentrated sulfuric acid and a reducer, thus producing a solution containing tetravalent vanadium. At least a portion of the trivalent vanadium solution is heated to 180.degree.-250.degree. C., thus producing a trivalent vanadium compound. If the trivalent compound produced is a solid, it is collected and solubilized in water and/or sulfuric acid. Then, unreacted sulfur is filtered out, thus obtaining a trivalent vanadium solution.

Abstract: Glycine and sodium sulfate decahydrate are separated from a starting aqueous solution containing glycine, sodium sulfate, and impurities, by forming a slurry which is a solid mixture of glycine and sodium sulfate decahydrate, followed by separation of the mixed crystals.

Abstract: A method for treating residues of barium sulfide or strontium sulfide leaching with waste sulfuric acid and hydrochloric acid, which method significantly decreases the amount of residual material which must be disposed of.

Abstract: A novel basic composite metal sulfate fiber, a process for the production thereof, and a resin and/or rubber composition which contains the basic composite metal sulfate fiber and gives a molded article which is improved in mechanical strength and/or flame retardancy and having an excellent appearance. The basic composite metal sulfate fiber has the formula (1),(Mg.sub.1-x M.sup.2+.sub.x).sub.6 (OH).sub.12-2y (SO.sub.4.sup.2-).sub.y.mH.sub.2 O (1)wherein M is at least one metal selected from the group consisting of Mn, Fe, Co, Ni, Cu and Zn, and x, y and m are respectively defined by 0.005<x<0.5, 0.8<y<1.2 and 0<m<4.

Abstract: A method for treating an aqueous stream containing a water-soluble, inorganic sulfide compound wherein the stream is contacted with oxygen at a pH in the range of less than about 12 and an oxygen to sulfur molar ratio greater than about 5 with an oxidizing catalyst at oxidation conditions selected to provide a high conversion of the inorganic sulfide compound to sulfate to thereby produce a substantially sulfide-free treated aqueous product stream.

Abstract: A process for producing NH.sub.3 and SO.sub.2 from ammonium sulfate, which comprises(i) reacting ammonium sulfate with a metal oxide or hydroxide at a temperature of not more than 200.degree. C. to form NH.sub.3, water and a metal sulfate and recovering NH.sub.3,(ii) decomposing the metal sulfate in the presence of a reducing agent to form a metal oxide and SO.sub.2 and recovering SO.sub.2, and(iii) recycling the metal oxide to step (i) as such or after it is converted to a metal hydroxide.

Abstract: Vanadium values useful for catalyst regeneration are recovered from compositions/materials comprised thereof, typically spent V.sub.2 O.sub.5 catalysts, by intimately contacting an aqueous suspension of such a material with a gaseous admixture of sulfur dioxide and oxygen, whereby a phase separation thus results, and recovering an aqueous phase constituting a solution of vanadium values.

Abstract: Barium sulfate which has a chemically reactive surface is produced by a precipitation of barium ions by means of sulfate ions in an aqueous medium. In order to provide barium sulfate as a filler having functional properties, the precipitation is effected as a coprecipitation in the presence of additional anions of water-soluble compounds, which anions are coprecipitable with barium ions to form difficulty soluble barium compounds. The reactive product which contains heteroatoms is subjected to an aftertreatment which is suitable for the use that is intended in a given case.

Abstract: A process of the present invention comprises dissolving rhodium black in sulfuric acid under heating, making the pH of the said sulfuric acid solution neutral or basic by adding an alkaline solution to the said sulfuric acid solution to precipitate rhodium as rhodium hydroxide, separating the rhodium hydroxide and dissolving it in nitric acid.The process is useful for preparing the rhodium nitrate solution which is not decomposed by heating or concentration to produce turbidity, and produces almost no changes when it is allowed to stand at room temperature for a long period of time. Since the rhodium nitrate solution has the excellent heat-stability and endurance for long term storage, the said solution can be employed as a useful rhodium source which does not decompose for a variety of applications.

Abstract: A process for converting sulfide ion present in a solution to innocuous, water soluble sulfur species is provided. The process basically includes the steps of contacting the sulfide ion with an oxidizing agent to oxidize it to the water soluble sulfur species and admixing a surface active agent with the solution in an amount sufficient to inhibit precipitation of elemental sulfur and to promote subsequent oxidation. To enhance the formation of the water soluble sulfur species and to speed up the reaction, the oxidation reaction is conducted under alkaline conditions.

Abstract: Stannous salts of a non-oxidizing anionic acid, e.g., stannous fluoborate or stannous sulfate, are prepared by reacting metallic tin with a preferably aqueous solution of such acid in the presence of a catalytically effective amount of finely divided catalyst particles, e.g., comprised of a precious metal, said catalyst particles providing hydrogen release at low overvoltages.

Abstract: Disclosed is an inorganic polymeric cationic ion exchange matrix which is the condensation polymerized reaction product of components including an alkyl compound of an element that has a valence of at least three, water, and a dopant having groups including an ion exchangeable moiety and a replaceable hydrogen. The ion exchange matrix is preferably made by adding the water to the alkyl compound first followed by the addition of the dopant, followed by heating to dryness. The resulting product is a powder or granule that can be used as an ion exchange matrix by placing it in a column and passing a solution through it which contains metal ions that are exchanged with ions on the polymer.

Abstract: A positive electrode for alkaline storage cells is disclosed. The active material for the positive electrode is a double hydroxide of the formula[M.sup.2+.sub.(1-x) Fe.sup.3+.sub.x (OH).sub.2 ].sup.x+ [(x/n)X.sup.n-..sub.y H.sub.2 O].sup.x-wherein x is in the range 0.05.ltoreq.x.ltoreq.0.4, M.sup.2+ is an oxidizable and reducible, and X.sup.n- is at least one anion. The double hydroxide has a pyroaurite-like double layer structure and is electrochemically resistant to iron poisoning. In a preferred embodiment, the double hydroxide comprises [Ni.sub.4 Fe(OH).sub.10 ].sup.+ [NO.sub.3.sup.-.yH.sub.2 O].sup.-. Methods for preparing positive electrodes having the double hydroxide active material are also disclosed.

Abstract: A continuous process for the manufacture of a metal salt solution is described which provides more economical products with higher quality than current processes. The process is safer, both to operating personnel and to the environment, than currently used processes. The process comprises feeding an aqueous metal compound slurry, e.g., a metal oxide/hydroxide slurry and a mineral acid, e.g., nitric acid, and water to a reactor which includes a zone of extreme mixing and agitation, most preferably a cross-pipe reactor provided with an optional static in-line mixer. A cross-pipe reactor provides complete and efficient reaction by providing greater surface area, high agitation and a long reaction time.

Abstract: Monovalent ions, especially chloride and fluoride, but also thallium, sodium and potassium are efficiently removed from ZnSO.sub.4 electrolyte by electrodialysis. Monovalent anions are removed using alternating monovalent anion permselective membranes and cation exchange membranes. Monovalent anions and cations are removed using alternating monovalent anion and monovalent cation permselective membranes. Electrodialysis is carried out under turbulent conditions, at up to 60.degree. C., a differential membrane pressure of less than 150 kPa, a current density of 10 to 500 A/m.sup.2, and a pH of less than 5.5. Where both chloride and fluoride are removed a pH of 3.5 to 5.5 is maintained.

Abstract: An improved process for reducing ammonium ion concentration in an ammonium ion-containing, acidic liquor is provided. The process includes the essential step of reacting ammonium ion with a persulfate.

Abstract: A process for selectively stripping and separating iron ions from an organic solvent (A) which comprises bringing the organic solvent (A) containing iron and zinc ions, and containing one or more compounds selected from the group consisting of alkyl phosphoric acid, alkyl-aryl phosphoric acid, alkyl thio phosphoric acid and alkyl-aryl thio phosphoric acid together with a petroleum hydrocarbon as a diluent, into contact with an aqueous solution containing NH.sub.4.sup.+ and F.sup.- ions so as to selectively strip the iron ions into the aqueous solution despite the coexistence of zinc ions.

Abstract: This method of obtaining an aqueous solution of metal values from an insoluble metal oxide is possible where the metal has a lower oxidation number in the solution than in the insoluble oxide, for example manganese (+2 and +4 respectively).The oxide, such as MnO.sub.2, is treated with hot mineral acid such as HCl in the presence of coal. After some hours, the liquid comes to contain most of the manganese as dissolved Mn(II) ion.

Abstract: The invention relates to basic chromium aluminum sulfates which are soluble in cold water and are of the general formulaCr.sub.x Al.sub.2-x (OH).sub.2 y. (SO.sub.4).sub.3-y.n H.sub.2 Owhere x is from 0.1 to 1.9, y is from 0.01 to 2 and n is from 4 to 24, and a process for the preparation thereof. The process comprises reacting chromium (III)--containing waste sulfuric acid having a water content of 20-50% by weight with aluminum oxide and/or aluminum oxide hydroxide and/or aluminum hydroxide at a temperature of 100.degree. to 200.degree. C. The molten product is converted to droplet form and allowed to solidify in free fall.

Abstract: Thiosalts contained in waste streams are oxidized to sulfate ions in the presence of sulfur-bound copper. Air oxidation of the waste stream is effected in a slurry of the copper compound, which may be CuS, Cu.sub.2 S or chalcopyrite, and continuous long term operation is possible without loss of catalytic activity and without catalyst degradation.

Abstract: Mercury is removed from sulfuric acid-bearing hot and moist smelting-plant or roasting-plant gases by cooling and scrubbing the hot gases by means of a concentrated sulfuric acid mist in order to sulfatize the mercury and to separate it from the gases. The cooling is carried out by vaporizing so much water or dilute sulfuric acid solution from the gases that the temperature of the gas drops to below the dew point, in order to produce a sulfuric acid mist which sulfatizes and washes the mercury, the gases being separated from the mist and directed to the sulfuric acid plant. The process can be carried out by means of nozzles installed in the pipe which feeds hot and moist sulfuric acid-bearing gases into the scrubbing tower of the sulfuric acid plant, water or acid obtained from the scrubbing tower being fed through the nozzles into the feed pipe in the form of a finely-divided mist.

Abstract: Aqueous alkaline sulfidic waste effluents are often subjected to air oxidation processes that for economic sizing oxidize the sulfides only to thiosulfates. Thiosulfates are still immediate oxygen demanders and thus their concentration in the effluent must normally be reduced to below a threshold level before the effluent can be discharged. The effectiveness of hydrogen peroxide for this purpose can be significantly improved both as to rate of reaction and extent of removal by employing a copper catalyst in solution.

Abstract: A method of recovering titanium from perovskite by leaching with a strong sulfuric acid solution is disclosed. The leaching produces a sulfate solution containing titanium and a calcium sulfate residue when the time and temperature of leaching are controlled as a function of the grind size of the perovskite and concentration of the sulfuric acid. The titanium-containing solution and the calcium sulfate residue are then separated. The titanium in the leach solution is precipitated by heating, as a mixture of titanium sulfates, which are then redissolved in water or dilute acid solution. Titanium dioxide may then be prepared by hydrolysis of the titanium in the resulting aqueous solution.

Abstract: Process for the manufacture of potassium sulphate from solutions containing magnesium chloride and potassium chloride from solutions, more particularly from mother liquors issuing from the treatment of carnallite. According to this process sodium sulphate and potassium chloride are added to the solutions so as to precipitate sodium chloride and schoenite (K.sub.2 SO.sub.4.MgSO.sub.4.6H.sub.2 O) and the schoenite is treated in a known manner to produce potassium sulphate.

Abstract: A process of preparing chromium (III) compounds from chromate and/or dichromate salts by forming a mixture of such salts, an acid, water and a reducing agent. Additional acid is added to the mixture which is then cooled selectively precipitating the salt of the anion of the acid and the cation of the chromate and/or dichromate salts which is separated from the solution containing the desired chromium (III) compound.

Abstract: A pharmaceutical composition comprising an amount, effective as an antacid, of a phosphate ion-containing hydrotalcite of the following formulaMg.sub.x Al.sub.2 (OH).sub.2x+6-n.sbsb.1.sub.z.sbsb.1.sub.-n.sbsb.2.sub.z.sbsb.2 (A.sub.1.sup.n.sbsp.1.spsp.-).sub.z.sbsb.1 (A.sub.2.sup.n.sbsp.2.spsp.-).sub.z.sbsb.2 .multidot.mH.sub.2 Owherein A.sub.1.sup.n.sbsp.1.spsp.- represents at least one anion having a valence of n.sub.1 selected from the group consisting of H.sub.2 PO.sub.4.sup.-, HPO.sub.4.sup.2.spsp.- and PO.sub.4.sup.-3, A.sub.2.sup.n.sbsp.2.spsp.- represents at least one anion having a valence of n.sub.2 other than the A.sub.1.sup.n.sbsp.1.spsp.-, and x, z.sub.1, z.sub.2, and m are positive numbers satisfying the following expressions2<x<40,0.05.ltoreq.z.sub.1 .ltoreq.2,0.1.ltoreq.z.sub.2 <2,0<m<40,0.5.ltoreq.z.sub.1 +z.sub.2 .ltoreq.

Abstract: The invention is a method for detecting the presence of or a predisposition to cancer in mammalian individuals. A trace element, specifically tin, is administered to the individual in the form of a radioactive isotope or a compound containing a radioactive tracer. The tin-bearing compound thereafter accumulates in the various bodily organs and is excreted. Indicative of the presence of cancer or a predisposition is the lack of accumulation of the radioactive tin compound in the thymus and lymphatic system of the mammal. By comparison of the radioisotope concentration in the urine and blood, the early detection of a precancerous or leukemic condition can be made. The method is applicable to a wide variety of mammals, including human beings.

Abstract: Waste products from the chrome-tanning of hides are washed and then chopped in water, with subsequent hydrolyzation at a pH of at least 10.5 and at boiling or near-boiling temperature. The resulting suspension is filtered to yield a polypeptide solution and a cake of solids consisting essentially of chromium hydroxide. The solution is neutralized, dehydrated, cooled and filtered to provide a virtually chromium-free proteinaceous substance usable as plant or animal feed; the solids are washed, filtered and acidified to provide chromium sulfate suitable for reutilization in tanning.

Abstract: Disclosed is a process for removing boron compounds from aqueous effluents. The effluents are contacted, under stirring, with a divalent metal sulphate Me.sub.I SO.sub.4 and a divalent metal hydroxyde Me.sub.II (OH).sub.2, the sulphate-hydroxyde couple being selected from the group consisting of BeSO.sub.4 --Ba(OH).sub.2 ; BeSO.sub.4 --Sr(OH).sub.2 ; BeSO.sub.4 --Ca(OH).sub.2 ; MgSO.sub.4 --Ba(OH).sub.2 ; MgSO.sub.4 --Sr(OH).sub.2 ; MgSO.sub.4 --Ca(OH).sub.2 ; CaSO.sub.4 --Ba(OH).sub.2 ; CaSO.sub.4 --Sr(OH).sub.2 ; SrSO.sub.4 --Ba(OH).sub.2 ; ZnSO.sub.4 --Ba(OH).sub.2 ; ZnSO.sub.4 --Sr(OH).sub.2 ; ZnSO.sub.4 --Ca(OH).sub.2 ; CdSO.sub.4 --Ba(OH).sub.2 ; CdSO.sub.4 --Sr(OH).sub.2 and CdSO.sub.4 --Ca(OH).sub.2. The sulfate Me.sub.I SO.sub.4 and the hydroxide Me.sub.II (OH).sub.2, by reaction with each other, cause the sulphate Me.sub.II SO.sub.4 and the hydroxide Me.sub.I (OH).sub.2 to precipitate.The amount of Me.sub.II (OH).sub.2 is at least stoichiometric in respect of the amount of Me.sub.I SO.sub.

Abstract: Soluble thiosulphates present in aqueous redox systems comprising at least one salt of an anthraquinone di-sulphonic acid and at least one water soluble compound of metal having at least two stable oxidation states, for example a vanadate, are converted to sulphates by introducing oleum or sulphuric acid into the lower half of a vessel containing said thiosulphate containing redox solution, wherein the sulphuric acid has a concentration of from 10-98% w/w H.sub.2 SO.sub.4 and the amount of said sulphuric acid is such that the gram molecular weight ratio of sulphuric acid to thiosulphate is from 1:2 to 1:3, and thereafter separating the sulphate formed for example by using a solubility lowering technique. The process is carried out at ambient temperature and at a temperature of from 70.degree. C. up to the boiling temperature of the acidic mixture.

Abstract: A liquid melt becomes converted to crystalline form at a particular temperature either spontaneously or when artificially nucleated. The liquid releases heat at crystallization. If the liquid is in a supercooled state when it begins to crystallize, its temperature will rise from the particular temperature at which it is nucleated.Another liquid material is mixed with the liquid to be crystallized. The liquid additive has properties of forming a metastable solid together with the crystallizing material. When the liquid additive exsolves, the crystalline aggregate is weakened and is easily decomposed into fragments of small size. The liquid additive materials may include monohydric alcohols, diols and triols. The liquid additive material may be included in the liquid to be crystallized, in small amounts, amounts to two percent (2%) to five percent (5%) being typical.

Abstract: Novel form of metal sulphate produced by alternate dehydration and rehydration, e.g., by cycling prismatic metal sulphate between 0.degree. C. and 70.degree. C., 20 minutes at each temperature, for 200 or more cycles, until a low-density powder is formed having a coral-like morphology at 8000 magnification.

Abstract: The present invention relates to methods for preparing a titanium tanning agent from sulphuric-acid titanium-ferriferous solutions and use thereof for leather tanning.The method for preparing a titanium tanning agent from titanium-ferriferous sulphate solutions comprises introduction, into said solution, of an oxidizing agent comprising a sulphuric-acid solution of a peroxy-titanium complex, follows by the addition of ammonium sulphate and sulphuric acid to precipitate a double salt of titanyl and ammonium sulphate in the monohydrate form (NH.sub.4).sub.2 TiO(SO.sub.4).sub.2.H.sub.2 O. The precipitation of this salt is preferably effected prior to its formation in an amount of 75-85% based on TiO.sub.2. The resulting salt is separated and washed; the filtrate and washings are combined and treated with ammonium sulphate to afterprecipitate the salt which is separated and recycled into the starting solution.

Abstract: Large proportion of available manganese ores contain high proportions of potassium. Electrolytic manganese dioxide (EMD) is manufactured from manganous sulphate obtained from naturally occuring manganese ores. Crystallographically EMD has to be essentially gamma phase and other phases, alpha and beta should be the bare minimum. High potassium content is, however, an obstruction in the way of getting gamma phase EMD. The present invention describes a method of making manganous sulphate solution with low level impurity of potassium from high potassium ores which comprises adding the reduced ore to spent electrolyte containing ferric ions and digesting same at pH 1-2 and temperature of 60.degree.-90.degree. C. for 1-4 hours, and thereafter again adding reduced ore to the digested product till pH is raised to 4-6.

Abstract: A method for preparing a high purity basic zirconium carbonate comprising(a) adding alkali or ammonium carbonate or alkali or ammonium hydrogen carbonate to an aqueous solution of zirconium sulfate to precipitate basic zirconium sulfate;(b) dissolving the basic zirconium sulfate in HCl solution and heating the solution to reprecipitate the basic zirconium sulfate;(c) suspending the precipitated basic zirconium sulfate in water and adding alkali or ammonium carbonate or alkali or ammonium hydrogen carbonate to the suspension to produce basic zirconium carbonate.The process provides a simple and economical means of producing a very high purity basic zirconium carbonate.

Abstract: A chemical, electro-chemical process for recovering meta values from a zinc- or lead-containing material comprises:in a solubilization stage, oxidizing the zinc- or lead-containing material by treating said material with a ferric chloride leach solution;when solubilized lead is present, separating it from the pregnant liquor forming an essentially lead free solution;dividing this essentially lead free solution into two portions;passing one portion of the essentially lead free solution into the anolyte compartment of a Zn.degree. producing electrolysis stage for use as the ferrous ion-containing anolyte thereof;separating iron from the second portion of the essentially lead free solution, forming an essentially iron free solution;passing the essentially iron free solution into the catholyte compartment of said Zn.degree. producing electrolysis stage for use as the catholyte thereof;conducting electrolysis in said Zn.degree.

Abstract: Basic zinc compound flake-like crystalline material suited for use in crystal-oriented electronic devices and method for preparation thereof comprising the steps of preparing a solution including at least zinc ions and sulfate ions, and causing precipitation of zinc sulfate crystals by causing a reaction of components of said solution with alkali when said solution is at a temperature in the range 50.degree. to 100.degree. C. and has a pH value of in the range 4 to 6.5.

Abstract: A process for treating sulfide ores to reduce the sulfur content or recover the metal content therefrom comprises the use of enzymatic action to solubilize the sulfur and metal content.A nutrient, such as a saccharide, is used along with yeast spores which feed on the sugar and produce enzymes which act on sulfur in the sulfide ore to cause the sulfur to go into solution and to dissolve those metals which are soluble in strongly acidic solution. Sulfuric acid can be formed from the sulfide ores or from free sulfur by reaction with water, with evolution of hydrogen sulfide gas. Oxidation of at least a portion of the hydrogen sulfide can be achieved to regenerate sulfuric acid.