Abstract: A titaniferous ore concentrate or slag is fed, together with sulfuric acid, into a heated pelletizer wherein the sulfation reaction occurs simultaneously with pellet formation.

Abstract: Cobalt is recovered as a finely-divided and anhydrous salt from impure, nickel-bearing, aqueous solutions of cobalt, by exposing the aqueous solution to oxidation at an elevated temperature in the presence of ammonia and the respective ammonium salt, the formation of cobalt (III) hexammine ions is catalysed with activated carbon or solid sulfides, a cobalt (III) hexammine salt is crystallized from the solution, the salt is separated from the solution and pyrolysed to form a cobalt (II) salt, and the released ammonia is returned to the oxidation stage.

Abstract: The present invention relates to a method of removing mercury-containing contaminations in gases by passing the gas to be purified through a filter bed which is devised to make the gas contact effectively. The method is characterized in that, the filter bed is consisted of specific material prepared by binding onto a carrier substance such as granulated pumice, with sulfurous substance as contamination absorbing agent, such as natural sulfide minerals subjected to a surface activation pretreatment, synthetized metal sulfides and sulfur.According to the present invention, it is intended to remove contaminations in gases, especially those containing vaporized mercury together with adsorption on the filter bed material, in such a mechanism that mercury, which has a high vapor pressure, is converted into its sulfide, which shows very low vapor pressure, by contacting the gas with sulfides of other metals or with sulfur.

Abstract: The invention relates to the re-extraction of a metal from an organic extraction solution in which the metal is present as a metal chloride complex bonded to an extractant. The organic extraction solution is contacted with an aqueous solution, to transfer metal ions and chloride ions to the aqueous solution. Sulphuric acid is added to the aqueous solution, which is subsequently heated to drive off hydrogen chloride and water. Metal sulphate is removed from the acidified aqueous solution.

Abstract: The present invention relates to a process for the recovery of manganese from aqueous acidic solution.The process comprises the steps of, (a) introducing into the solution peroxymonosulphuric acid (PMS) in a plurality of stages, normally from 2 to 6, often in the range of from 110 to 160% of the amount theoretically needed to oxidise the manganese to the Mn (IV) oxidation state, (b) introducing from 100 to 133% of the theoretical amount of neutralising agent to neutralise the PMS introduced in step (a), preferably in a single addition and prior to the introduction of the second stages of PMS and, (c) separating precipitated manganese salt from solution. The demanganisation reaction is preferably carried out at a temperature of above 60.degree. C. usually in the range of 70.degree. to 90.degree. C.An aqueous acidic manganese-containing solution can be obtained by leaching ores or scrap metal with strong mineral acids.

Abstract: A monovalent thallium compound is converted to a trivalent thallium compound by treating the thallium (I) compound with molecular oxygen in the presence of a Group VIII noble metal catalyst in a liquid medium and in the presence of a promoter comprising at least one member selected from the group consisting of alkyl ammonium salts, to oxidize the thallium (I) compound to a thallium (III) compound.

Abstract: A method of improving the surface characteristics of a formed article of magnesium oxychloride or magnesium oxysulfate cement is shown in which molded articles of magnesium oxychloride or magnesium oxysulfate are treated with water at temperatures of 90.degree. F. to 212.degree. F. (32.2.degree. C. to 100.degree. C.) for periods of 1 to 30 minutes or longer to prevent the formed article from efflorescing.

Abstract: Process for purifying an iron containing zinc sulfate solution which comprises precipitating iron from said solution as a slurry in at least one of the following forms at a pH which is maintained lower than 4: basic sulfate, jarosite or goethite; filtering said slurry on a planar horizontal filter and forming a cake on said planar filter; washing the cake directly on the planar filter with water supplied onto the cake without forming a newslurry with washing water and thus freeing the cake from water soluble zinc and copper compounds promptly before hydrolysis thereof insolubilizes said compounds as basic sulfates, whereby the solid residue in the cake does not contain substantially more insoluble zinc content than it contained in the slurry being fed to the filtration.

Abstract: Process for removing chlorine from an acidic zinc or cadmium sulphate solon, comprising adding thereto acid of Caro or an ammonium or alkali metal salt thereof.

Abstract: An improved process for preparing a metallic sulphate in a reaction zone from mixing of the corresponding metallic sulphide concentrates with ammonium sulphate and heating. Heating preferably includes directly contacting the mixture with products of combustion of a heating fuel at temperatures between about 150.degree. C and about 480.degree. C. The products of combustion may be diluted with a gas, and the metallic sulphate of the corresponding metallic sulphide may be initially mixed with the mixture to inhibit the development of semi-fluid conditions in the reaction of the metallic sulphide concentrates with ammonium sulphate.

Abstract: A monovalent thallium compound is converted to a trivalent thallium compound by treating the thallium (I) compound with an organic hydroperoxide in the presence of a Group VIII noble metal catalyst in a liquid medium and in the presence of a promoter comprising a member selected from the group consisting of alkali metal compounds and heterocyclic tertiary amines, to oxidize the thallium (I) compound to a thallium (III) compound.

Abstract: A monovalent thallium compound is converted to a trivalent thallium compound by treating the thallium (I) compound with molecular oxygen in the presence of a Group VIII noble metal catalyst to oxidize the thallium (I) compound to a thallium (III) compound.

Abstract: A monovalent thallium compound is converted to a trivalent thallium compound by treating the thallium (I) compound with an organic hydroperoxide in the presence of a Group VIII noble metal catalyst in a liquid medium to oxidize the thallium (I) compound to a thallium (III) compound.

Abstract: A mono-valent thallium compound is converted to a trivalent thallium compound by treating the thallium (I) compound with molecular oxygen in the presence of a Group VIII noble metal catalyst and in the presence of a promoter comprising an alkali metal compound to oxidize the thallium (I) compound to a thallium (III) compound.

Abstract: Process for removing impurities selected from the group consisting of manese, cobalt, nickel and thallium from an acidic zinc or cadmium solution comprising adding thereto acid of Caro or an ammonium or alkali metal salt thereof.

Abstract: A process for separating cobalt from nickel in an aqueous acid solution containing the above metals, which comprises contacting said solution with an organic phase comprising (a) 65-98% by volume of a concentrated alpha-hydroxyoxime extractant, a 1% by volume solution of which in xylene has per liter a maximum loading capacity of about 0.864 g. of copper, and (b) 2-35% by volume of an organophosphoric acid of the general formula: ##STR1## wherein R.sub.1 represents an alkyl, aryl or aralkyl radical, while maintaining the pH of said solution between 1 and 6, whereby cobalt is extracted from the aqueous phase to the organic phase and separating the resultant cobalt pregnant organic phase from the aqueous phase.

Abstract: A process for removing sulfuric acid from reaction mixtures containing sulfuric acid and .epsilon.-caprolactam by treating the sulfuric acid with ammonia and sulfur dioxide to produce ammonium sulfate salts and reducing the ammonium sulfate salts to ammonia and sulfur dioxide.

Abstract: An improved technique for purifying a solution of metallic salts from copper and cadmium contained in such solution is described. A bed of zinc granules is disposed on a grid at the bottom of a vertically arranged, cylindrical reaction chamber. The solution to be purified is pumped upwardly through the grid and the zinc bed at a speed in the range of 0.08-0.5 m/sec. to impart a turbulent motion to the zinc granules throughout the height of the reaction chamber. The turbulence causes the copper-cadmium cake adhering to the zinc particles during the reaction to separate from the granules, so that the separated cake flows out of the reaction chamber with the purified liquid to be quickly and easily removed therefrom.

Abstract: A process of producing calcium aluminate monosulfate hydrate by reacting a mixture of a lime component, an alumina component, a calcium sulfate component, and water at a temperature of from about 100.degree. C. to about 200.degree. C.By the process of this invention, the aimed product having a high purity is obtained at a high yield without need of high temperature for the reaction. The product obtained is useful as building materials.

Abstract: An improved supported thorium sulfate catalyst is prepared by converting a thorium compound impregnated in the carrier to thorium sulfate in situ. The improved catalyst is used in the production of N-alkylated amines, by contacting an alkanol with a primary or secondary amine, in the vapor phase.

Abstract: Process for recovering sulfur from waste waters containing sulfuric acid, comprising reacting in a first step, the waste water with an aqueous solution of ammonium sulfite, separating the formed sulfur dioxide from the solution, reacting the resulting solution in a second step with calcium oxide to form calcium sulfate and an aqueous ammonia solution, vaporizing ammonia therefrom, reducing the calcium sulfate by means of carbon to form calcium oxide and sulfur dioxide, contacting said vaporized ammonia with said sulfur dioxide and with water, thereby forming an aqueous solution of ammonium sulfite, which is joined to that used in the first step and recycling at least a part of the calcium oxide obtained by reduction of the calcium sulfate to the second step.

Abstract: A process for the production of substantially pure hydrated nickel sulphate which involves reacting sulphuric acid with nickel chloride at the boiling point of the reaction mixture and partially removing formed hydrogen chloride gas. The reaction mixture is clarified to separate impurities, the formed nickel sulphate is crystallized from the clarified mixture, and the mother-liquor obtained at this stage recycled to an earlier stage of the process. The crystals of nickel sulphate are dried and the mother-liquid obtained at this stage, then recycled to an earlier stage of the process. The hydrated nickel sulphate obtained is substantially pure and essentially free of chloride ions.

Abstract: In the production of a solid-free solution of titanyl sulfate by digesting ilmenite or titanium slag with sulfuric acid, and filtering the resulting solid-containing solution of titanyl sulfate to separate the solids, the improvement which comprises filtering the solution under a pressure of about 1 to 16 bars to form a filter cake of a thickness of about 10 to 35 mm. The filter cake is washed with about 0.1 to 0.5 m.sup.3 of water per m.sup.3 of filtrate, the wash water is passed through the filter cake at a flow rate of about 0.1 to 1.2 m/h under a pressure of about 1 to 16 bars, and the filter cake is then squeezed to a solid content of about 50 to 70% by weight.

Abstract: A process for the joint production of titanium dioxide and sodium tripolyphosphate from ores of titanium and phosphorus, and from sulphuric acid, in which the titanium dioxide is produced by the "sulphate process" and the impure dilute aqueous solution of sulphuric acid resulting therefrom is concentrated and used in the initial attack of phosphatic ones to provide a solution containing vanadium and chromium which can be removed without requiring any preventive conversion. The resulting sodium phosphate is then converted to sodium tripolyphosphate in a known way.

Abstract: A process for removing chlorine from a solution of zinc sulfate, in which the pH of the solution is reduced to below 2.6 with sulfuric acid. Cupric ions are established in the solution in an amount such that after removal of the chlorine by precipitation as cuprous chloride, there remains an excess of cupric copper in the solution which is greater than 0.5 g/l. The cupric ions can be added by adding cupric sulphate and zinc powder, or cupric salt and metallic copper, or cupric copper followed by cuprous oxide. The cuprous chloride precipitate is collected and washed and treated with sodium hydroxide in an amount to raise the pH to more than 7, thereby to precipitate cuprous oxide which is separated by filtration.

Abstract: A process and apparatus for producing certain metal salts in very fine particulate form. The process comprises cooling a solution of metal salt until the solution freezes and thereafter evaporating the solvent under very low pressure. The process is particularly applicable to salts of tungsten and nickel from which sub-micron particles of tungsten and nickel can be produced.

Abstract: A method of producing hydrogen and oxygen by splitting water in a thermocical cycle, according to which in a first method stage a gas mixture of from 1 to 50 parts by volume of steam and 2 parts by volume of sulfur dioxide is reacted at a temperature within the temperature range of from 200.degree. to 400.degree. C with an oxide of one of the metals manganese, iron, cobalt, nickel, zinc or cadmium for forming a metal sulfate and for freeing hydrogen gas. Thereupon the hydrogen gas is in a manner known per se separated from the residual gas mixture and in a second method stage after conversion of the metal oxide to a metal sulfate, the metal sulfate for purposes of decomposition or disintegration and for forming a metal oxide, sulfur dioxide gas and oxygen gas, is heated to a temperature within the temperature range of from 700.degree. to 1000.degree. C. Thereupon the oxygen gas is separated from the sulfur dioxide gas in a manner known per se.

Abstract: A dilute aqueous slurry of hydrated zinc oxide is subjected to heat and pressure to obtain solids having improved filtering characteristics. The process is especially useful in the treatment of neutralized waste liquor from the viscose rayon system to provide a more economical method for the recovery of zinc sulfate.

Abstract: A thermochemical reaction cycle for the generation of hydrogen from water comprising the following sequence of reactions wherein M represents a metal:CH.sub.4 + H.sub.2 O .fwdarw. CO + 3H.sub.2 (1)co + 2h.sub.2 .fwdarw. ch.sub.3 oh (2)ch.sub.3 oh + so.sub.2 + mo .fwdarw. mso.sub.4 + ch.sub.4 (3)mso.sub.4 .fwdarw. mo + so.sub.2 + 1/2o.sub.2 (4)the net reaction is the decomposition of water into hydrogen and oxygen.

Abstract: Nickel values are recovered from ammoniacal solutions in a continuous solvent extraction process utilizing a plurality of elongated columns containing a multiplicity of spaced-apart, perforated trays, or decks. The organic solvent constitutes an oxime and at least one species of hydrocarbon diluent having from three to seven carbon atoms per molecule. Elevated pressures in the range of about 100 to 1,000 psig. (7.03 to 70.3 kg/sq.cm.) are utilized.

Abstract: A thermochemical reaction cycle for the generation of hydrogen from water comprising the following sequence of reactions wherein M represents a metal and Z represents a metalloid selected from the arsenic-antimony-bismuth and selenium-tellurium subgroups of the periodic system:2MO + Z + SO.sub.2 .fwdarw. MZ + MSO.sub.4 (1)mz + h.sub.2 so.sub.4 .fwdarw. mso.sub.4 + h.sub.2 z (2)2mso.sub.4 .fwdarw. 2mo + so.sub.2 + so.sub.3 + 1/20.sub.2 (3)h.sub.2 z .fwdarw. z + h.sub.2 (4)h.sub.2 o + so.sub.3 .fwdarw. h.sub.2 so.sub.4 (5)the net reaction is the decomposition of water into hydrogen and oxygen.

Abstract: A method is disclosed wherein a water stream is improved by oxidizing sulfur and/or the sulfur content of sub-six-sulfur-containing impurities in the stream to sulfate. In the method, the stream is contacted with molecular oxygen under particular conditions which include an elevated temperature, a substantial oxygen gas partial pressure, a pH of at least 9.6 and the substantial absence of a heavy metal oxidation catalyst. For each gram atom of sub-six sulfur, the contact mixture must contain at least one equivalent of a strong inorganic base such as sodium hydroxide.