Abstract: A process for recovering pig iron from iron-containing concentrates produced from iron-containing ores and sands by forming agglomerates and reducing them in a natural gas smelter, in which the process makes maximum utilization of heat created in and by the process.

Abstract: There are provided processes for extracting aluminum ions from aluminous ores. Such processes can be used with various types of aluminous ores such as aluminous ores comprising various types of metals such as Fe, K, Mg, Na, Ca, Mn, Ba, Zn, Li, Sr, V, Ni, Cr, Pb, Cu, Co, Sb, As, B, Sn, Be, Mo, or mixtures thereof.

Abstract: A process for the recovery of nickel and cobalt from nickel and cobalt containing ores, including the steps of first leaching a laterite ore and/or a partially oxidized sulfide ore with an acid solution to produce a pregnant leach solution containing at least dissolved nickel, cobalt and ferric ions, and subsequently leaching a sulfide ore or concentrate with the pregnant leach solution to produce a product liquor. Alternatively, the laterite ore and/or partially oxidized sulfide ore can be leached in a combined leach with the sulfide ore or concentrate. The ferric ion content in the pregnant leach solution or in the combined leach is sufficient to maintain the oxidation and reduction potential in the sulfide leach high enough to assist in leaching nickel from the sulfide ore or concentrate.

Abstract: The invention provides a method for the Industrial purification of a low-grade polyvalent cation feed stream of purity P1, by the formation of a polyvalent cation-double-salt precipitate of purity P2 and a polyvalent cation solution with purity P3, wherein P2>P1>P3, said method comprising the steps of: a) forming, from said feed, a medium comprising water, polyvalent cation, a cation selected from the group consisting of ammonium, cations of alkali metals, protons and a combination thereof, and anions; which formed medium is further characterized by the presence of (i) a double-salt precipitate comprising a polyvalent cation, at least one of said cations and at least one of said anions; and (ii) a polyvalent cation solution; and wherein the concentration of said anions is higher then 10% and the ratio between the concentrations of said cation to said anion in said polyvalent cation solution is within Zone DS as herein defined; and b) separating at least a portion of said precipitate from said solution.

Abstract: Decomposition of methane to produce carbon monoxide-free hydrogen is accomplished using un-supported, nanometer sized, hydrogen reduced, nickel oxide particles made by a precipitation process. A nickel compound, such as NiCl2 or Ni(NO3) is dissolved in water and suitably precipitated as nickel hydroxide. The precipitate is separated, dried and calcined to form the NiO catalyst precursor particles.

Abstract: There is provided an improvement in a process for producing cobalt (III) hexammine sulphate which process comprises oxidatively pressure leaching nickel cobalt sulphides in an ammoniacal ammonium sulphate solution. The nickel and cobalt sulphides are oxidized to sulphates, and an ammoniacal leach liquor in which dissolved cobalt is predominantly in the (III) oxidation state is produced. The ammoniacal leach liquor is combined with ammonia to precipitate the triple salt of cobalt (III) hexammine sulphate, nickel (II) hexammine and ammonium sulphate which is further treated to produce a crystalline cobalt (III) hexammine sulphate and a nickel enriched leach liquor. The improvement involves the provision of a second oxidative pressure treatment effective to maximize the formation of the desired cobalt (III) hexammine ion, prior to the triple salt precipitation step.

Abstract: There is provided an improvement in a process for producing cobalt (III) hexammine sulphate which process comprises oxidatively pressure leaching nickel cobalt sulphides in an ammoniacal ammonium sulphate solution. The nickel and cobalt sulphides are oxidized to sulphates, and an ammoniacal leach liquor in which dissolved cobalt is predominantly in the (III) oxidation state is produced. The ammoniacal leach liquor is combined with ammonia to precipitate the triple salt of cobalt (III) hexammine sulphate, nickel (II) hexammine and ammonium sulphate which is further treated to produce a crystalline cobalt (III) hexammine sulphate and a nickel enriched leach liquor. The improvement involves the provision of a second oxidative pressure treatment effective to maximize the formation of the desired cobalt (III) hexammine ion, prior to the triple salt precipitation step.

Abstract: An improved process of hydrometallurgical treatment of laterite ores predominantly of the limonitic type for the recovery of nickel and cobalt using sulphuric acid. In order to obtain high extractions of these metals while treating these ores in their humid state, in reaction times of up to 60 minutes, temperatures of up to 270° C. and corresponding pressures of up to 800 psia are used. In the present invention, a significant portion of the “mother liquor” emanating from the pressure leaching reaction is recycled to the feed preparation stage thereby substituting for all or a major proportion of the water that must be added. Concomitantly with the major savings in water requirements, a significant reduction in new sulphuric acid requirements is effected along with a corresponding saving in limestone and lime required for subsequent neutralizations. The amount of process water released to the environment is significantly reduced or eliminated.

Abstract: A hydrometallurgical process is provided for leaching nickeliferous laterite ores at temperatures below the boiling point of the pulp and at atmospheric pressure. The high iron fraction of the laterite, referred to as limonite, is first contacted with concentrated sulfuric acid to partially or completely dissolve the iron and nickel into solution. A reducing agent is used to keep the redox potential in solution below 1000 mV to enhance cobalt dissolution and more advantageously between 1000 and 900 mV to avoid reduction of ferric iron. Further mixing of the leach slurry in the presence of sodium, potassium, or ammonium allows formation of iron jarosite at ambient pressure. The resulting acid from iron hydrolysis is neutralized with the low iron fraction of the laterite ore (saprolite), thereby dissolving nickel into solution. The resulting final leach slurry can then be treated with conventional methods to recover nickel and cobalt from solution.

Abstract: The invention relates to a method for leaching zinc concentrate in atmospheric conditions in the presence of trivalent iron. It is essential that the zinc concentrate is fed into conditions where in addition to trivalent iron, there are also jarosite nuclei. The sulfuric acid content of the leaching step is maintained within the region 10-40 g/l, and the temperature within the region 80° C.—the solution boiling point, and into the leaching step there is fed oxygen, so that the zinc concentrate is dissolved and the iron is precipitated as jarosite.

Abstract: A process for producing cobalt metal powder from nickel-cobalt sulphides wherein said nickel-cobalt sulphides are leached in an ammoniacal ammonium sulphate solution under an elevated pressure of an oxygen bearing gas, at a temperature of at least 80° C., with an effective ammonia to metals mole ratio in the range of 5:1 to 6.5:1 to oxidize the nickel and cobalt sulphides to sulphates, and to produce an ammoniacal leach liquor in which dissolved cobalt is predominantly in the (III) oxidation state, and an ammoniacal ammonium sulphate leach residue containing a cobalt (III) hexammine sulphate-calcium sulphate double salt.

Abstract: There is provided a process for the recovery of cobalt as cobalt (III) hexammine sulphate, comprising adding an effective amount of a calcium sulphate slurry to an ammoniacal ammonium sulphate solution containing cobalt (III) hexammine sulphate to thereby selectively precipitate a cobalt (III) hexammine sulphate-calcium sulphate double salt. The solution containing other base metal impurities is separated from the cobalt (III) hexammine sulphate-calcium sulphate double salt precipitate. An effective amount of an ammonium carbonate containing solution is added to the double salt precipitate to thereby redissolve cobalt (III) hexammine sulphate and precipitate calcium carbonate.

Abstract: A process is provided for the manufacture of ferric sulphate compounds from ferrous sulphate in a closed vessel containing a liquid phase and a vapor phase, the process comprising the oxidation of Fe.sup.++ to Fe.sup.+++ under pressure utilizing commercial oxygen in the closed vessel using NOx as a catalyst where x is a number between 1 and 2 inclusive of 1 and 2 and wherein the process comprises the following reactions: ##EQU1## wherein n is any integer greater than or equal to two (2) and y is any integer which is equal to, or greater than zero (0) and less than 3n and wherein the oxidation of Fe.sup.++ is affected by spraying the liquid phase including a solution containing Fe.sup.++ introduced to the closed vessel, through a reacting cloud comprising NO, NO.sub.2 and O.sub.2 enclosed in the vapor space of the closed vessel and wherein substantially only Ferric ions is present in the liquid phase in the closed vessel relative to the amounts of Ferric and Ferrous ions prior to the addition of FeSO.sub.4.

Abstract: A method for the recovery of copper from copper-containing materials, for example, scrap, ores or dust. An aqueous cupric tetrammine sulfate lixiviant is contacted with the copper-containing material to produce a leachate containing cuprous, nickel, and zinc ions, ammonium sulfate and free ammonia. Copper can be recovered from the leachate by electrolysis. Nickel and zinc can be precipitated from the resulting spent electrolyte by oxidizing substantially all of the cuprous ions in the copper ammine sulfate solution to cupric ions and lowering the pH of the solution to a range from about pH 7.5 to about pH 8.0 in order to form a precipitate. Alternatively, copper sulfate can be added to the cupric ammine sulfate-containing solution in order to form nickel and/or zinc containing precipitate.

Abstract: A process for the manufacture of ferric sulphate from ferrous sulphate in a closed circuit or vessel comprising a liquid phase and a vapor phase, wherein the vapor phase is essentially a closed system, the process comprising the oxidation between about 70.degree. C. to about 150.degree. C. of Fe.sup.++ .fwdarw.Fe.sup.+++ under pressure utilizing commercial oxygen in the closed circuit or vessel using (NO.sub.x) as a catalyst where x is a number between 1 and 2 inclusive of 1 and 2, and wherein the process comprises the following reactions:1) NO+1/2O.sub.2 .fwdarw.NO.sub.2, and2) 2FeSO.sub.4 +H.sub.2 SO.sub.4 +NO.sub.2 .fwdarw.Fe.sub.2 (SO.sub.4).sub.3 +H.sub.2 O+NO,and wherein the oxidation of Fe.sup.++ is affected by spraying the reacting solution containing Fe.sup.++ introduced to the closed circuit or vessel through a reacting cloud in the vapor phase comprising NO, NO.sub.2 and O.sub.2 enclosed in the vapor phase of the closed circuit or vessel and wherein substantially only Fe.sub.2 (SO.sub.4).sub.

Abstract: A process for the manufacture of ferric sulphate from ferrous sulphate in a closed circuit or vessel comprising a liquid phase and a vapor phase, the process comprising the oxidation between about 70.degree. C. to about 150.degree. C. of Fe.sup.++ .fwdarw.Fe.sup.+++ under pressure utilizing oxygen in the closed circuit or vessel using (NO.sub.x) as a catalyst where x is a number between 1 and 2 inclusive of 1 and 2, {NO.sub.x being a mixture of NO and NO.sub.2 } and wherein the process comprises the following reactions:1) NO+1/2O .sub.2 .fwdarw.NO.sub.2, and2) 2FeSO.sub.4 +H.sub.2 SO.sub.4 +NO.sub.2 .fwdarw.Fe.sub.2 (SO.sub.4).sub.3 +H.sub.2 O+NO, and wherein the oxidation of Fe.sup.++ is affected by spraying the reacting solution (taken for example from the bottom of the vessel or closed circuit containing the reacting solution) through a reacting cloud in the vapor phase comprising NO, NO.sub.2 and O.sub.2 enclosed in the vapor space of the closed circuit of vessel.

Abstract: A process for recovery of metal from a feedstock comprising copper is provided. The process comprises the steps of:(a) contacting the feedstock with an aqueous mixture comprising ammonium nitrate having a concentration greater than about 1.5M and sulphuric acid having a concentration greater than about 6M at a temperature of from about 105.degree. C. to about 130.degree. C., to produce a first residue comprising a cuprous salt and a leachate comprising copper;(b) separating the residue from the leachate; and(c) electrowinning copper from the leachate.The process may also be used advantageously to recover iron present in the feedstock in a form other than jarosite.

Abstract: The invention relates to a process for recovering non-ferrous metal values such as nickel, cobalt, copper, zinc, manganese and magnesium from material containing said metals, by converting the non-ferrous metal values into sulphates by using melt and melt coating sulphation and recovering them as metal compounds by a process entity based on a melt and melt coating sulphation.

Abstract: The invention relates to a process for the recovery of metal values contained in a ferric gangue.The process comprises the following stages:(a) dissolution of the metal values from the ferric gangue with sulphuric acid;(b) recovery of the metal value or values by a method which is known per se,(c) evaporation of the acid ferric solution resulting from stage (b) so as to increase the acidity to a value of between about 50 and 100%,(d) crystallization from this solution, at a temperature of between -10 and 50.degree. C., of a hydrated iron sulphate of formula Fe.sub.2 (SO.sub.4).sub.3.9H.sub.2 O.Application to the recovery of strategic metals.

Abstract: A method of processing manganese ore by adding the ore to an aqueous solution of acid and H.sub.2 O.sub.2 to form a leach pulp. The leach pulp is agitated for a predetermined time period at predetermined temperatures. The leach pulp is then separated into a solid fraction and a liquid fraction containing solubilized metals. The solubilized metals are then recovered from the liquid fraction.

Abstract: A nickel-containing ore is leached with sulfuric acid to dissolve nickel and associated metallic values into the sulfuric acid to form a leachate, the sulfuric acid further containing a source of the monovalent cations sodium, potassium or ammonium to suppress solubilization of aluminum ions in the ore. The leaching process is conducted at elevated temperatures of from about 200.degree. C. to about 300.degree. C., and at elevated pressures. In such leaching process, the monovalent cations are present in the leaching liquid prior to the initiation of leaching, to achieve an aluminum content of the leachate of less than about 0.5 grams per liter.

Abstract: A process is provided for the recovery of vanadium and nickel values from petroleum residues and, in particular, from Flexicoke. In the process, Flexicoke is blended with an alkali metal source, such as sodium sulfate or sodium carbonate, and then roasted in an oxygen-containing gas until carbon is removed and a fused mixture is obtained. Thereafter, the vanadium is leached from the mixture with an aqueous solution, and nickel is contained in solids remaining from the leaching.

Abstract: The object of this invention is a process for separating metal compounds, even in small percentages, from dusts and sludges, by reduction.The process may be successfully applied to the selective separation of vanadium pentoxide contained in small fractions in the ashes of heavy fuels, as well as to the separation and/or passivation of chromium compounds, of which the polluting characteristics are well-known.Separation is obtained by means of a reduction tower containing preferably iron scraps or shavings, adjusting on one side the pH of the input solutions according to their compositions, and on the other side the speed with which the solution passes through the reduction tower, so as to obtain a specific pH value of the output, again depending on the type of metal to be treated (FIG. 2).

Abstract: A process for enhancing recovery of metals, especially cobalt, from spent hydroprocessing catalysts when the spent catalyst particles are first roasted at between 400.degree. C. and 600.degree. C. and then contacted with a first aqueous solution of ammonia and an ammonium salt to recover nickel, cobalt, molybdenum, tungsten, and vanadium. The once-leached spent hydroprocessing catalysts are again leached by contacting them with a second aqueous solution of ammonium sulfate at a pH of 1 to 4.

Abstract: A hydrometallurgical process is provided to electrogalvanize steel, utilizing primary and secondary zinc sources. The process consists of leaching the feed in a mildly acidic solution. The zinc is selectively recovered from the leach liquor in a solvent extraction system and thereafter stripped from the solvent using a stronger acidic solution to provide a strip solution which is fed to an electrogalvanizing bath for electrogalvanizing steel products, e.g., sheet steel, using insoluble anodes. Acidic solutions and organic solvent are recycled in the process.

Abstract: The Abstract of the Invention is a method of making a solution of the nitrates of iron and chromium from a spent catalyst containing oxides of iron and chromium, which method comprises:(a) dissolving the catalyst in sulphuric acid;(b) reacting the resulting sulphates solution with a source of nitrate ions and of cations of which the sulphate is of low solubility, whereby to precipitate such sulphate;(c) separating the sulphate, whereby to give a nitrates solution of low sulphate content.

Abstract: A process for thermal activation of chalcopyrite-pyrite ore concentrates for activation of iron values in both chalcopyrite and pyrite constituents whereby said iron values can be selectively removed in a subsequent acid leach. Controlled oxidizing conditions are maintained in an oxidizing heating zone for removal of up to about 90% of total sulfur to be removed for conversion of pyrite and chalcopyrite to their acid-leachable forms, measured by a preferable oxidation of 10 to 15% of iron in the concentrate to ferromagnetic oxides, whereby remaining total sulfur to be removed is removed in a reducing zone with the assistance of a low H.sub.2 S/(H.sub.2 +H.sub.2 S) ratio by scavenging of H.sub.2 S by said oxides.

Abstract: A process for precipitation of iron as a jarosite compound from sulfate solution in which said solution fed sequentially through a plurality of reaction zones for oxidation and hydrolysis of ferrous sulfate in the presence of alkali-metal or ammonium ions for jarosite precipitation and simultaneous generation of sulfuric acid is subjected to a "reverse temperature profile", i.e., higher temperature in the last reaction zone than in the first reaction zone, by injection of steam to the last reaction zone.

Abstract: A process for precipitating iron as a jarosite from a sulphate solution containing ferric iron, free acid and valuable non-ferrous metals, characterized by cooling the solution; partially neutralizing the free acidity, and then clarifying the solution; heating the clarified solution to a temperature not exceeding the boiling point at atmospheric pressure, in the presence of at least one ion selected from the group consisting of sodium, potassium and ammonium ions, and in the presence of recycled jarosite, and without the addition of any further neutralizing agent, so that substantially all of the ferric iron is precipitated as a jarosite; and separating precipitated jarosite from the solution; thereby producing a jarosite contaminated with only minor amounts of non-ferrous metals, and a solution which may be further processed by established procedures for the recovery of dissolved valuable non-ferrous metals therefrom. The invention also contemplates a dilution step, and recycle of jarosite.

Abstract: Ammonium jarosite is converted to hematite or magnetite and ammonium sulphate. The invention can be used for removing iron from a feed solution containing dissolved ferrous sulphate. The feed solution is treated with ammonium sulphate and oxygen to precipitate ammonium jarosite which is then separated from the treated solution to produce an ammonium jarosite slurry and a separated solution containing sulphate ions. The ammonium jarosite slurry is treated with ammonia to convert the ammonium jarosite to hematite or magnetite and ammonium sulphate solution. The ammonium sulphate solution is separated from the hematite or magnetite, and a portion of the separated ammonium sulphate solution is recycled to the ammonium jarosite precipitation step, the remaining portion of the separated ammonium sulphate solution being recovered.

Abstract: Copper is separated from nickel present therewith in a sulfate solution by neutralizing to precipitate all the copper and some nickel as basic compounds, and thereafter reducing the copper in the basic compounds to elemental form through formation of cuprous sulfite and thermal dissociation of the latter.

Abstract: A process for recovering metallic cobalt from an aqueous ammoniacal solution containing dissolved cobalt and other metals as ammine sulphates with substantially all the dissolved cobalt being in cobaltic form. The process includes contacting the solution with a water immiscible liquid ion exchange reagent dissolved in an inert organic diluent to selectively substantially completely extract the other metals from the solution and produce an organic extractant loaded with the other metals and an aqueous cobalt bearing raffinate substantially free of the other metals. The cobalt bearing raffinate is separated from the loaded organic extractant and the loaded organic extractant is washed to remove substantially all ammonia therefrom. The other metals are stripped from the washed organic extractant which is then recycled to treat further solution. Cobalt is recovered from the raffinate.

Abstract: This invention relates to a process for hydrometallurgical treatment of concentrates of sulphides of copper, nickel, cobalt, lead and iron and copper-containing mattes. A first embodiment of the process includes subjecting a finely ground slurry of a sulphide concentrate to an oxidation leach at elevated temperature and pressure in the presence of an oxygen-bearing gas to preferentially leach cobalt and nickel and to convert galena to lead sulphate. The reaction mixture is heated to a further elevated temperature, in the absence of oxygen, to convert a portion of chalcopyrite to insoluble simple copper sulphides and ferrous sulphate solution and to decompose complex insoluble ferric compounds. The resulting mixture is subjected to differential flotation whereby a lead concentrate and a copper concentrate are obtained.

Abstract: A method for the recycle treatment of nickel plating waste water, in order to efficiently recover the nickel components from waste water which has been used for the washing of nickel plated products in a form re-usable as a nickel plating solution as such, wherein the nickel plating waste water is mixed with an aqueous alkaline component so as to remove, by precipitation in the form of hydroxides, contaminating metal ions other than nickel; the filtrate so obtained is treated through an ion exchange process so as to obtain an aqueous solution of nickel salts containing excess free sulfuric acid, a portion of which is then treated with alkali so as to precipitate nickel hydroxide which is separated in the form of nickel hydroxide through filtration by means of a centrifuge; the nickel hydroxide so obtained is then added to the rest of the aqueous nickel salt solution for neutralization with the free sulfuric acid contained therein to form nickel sulfate; and the free sulfuric acid is then removed so as to obta

Abstract: Certain mineral values are recovered from source material such as ore, scrap metal, and mixtures in the presence of another metal thereof by aqueous ammonia leaching solution, and the mineral values are precipitated by ammonia from said solution as a complex, and the mineral values are recovered from said complex.

Abstract: A hydrometallurgical process for treating iron containing metal sulfides for rendering iron and non-ferrous metal values active and amenable for selective extraction and separate recovery. Sulfur values can be controllably produced as elemental sulfur or as sulfuric acid to supply acid requirements of the process, while substantially obviating the discharge of sulfur-containing gases to the atmosphere. Ores and concentrates of the sulfides are thermally activated by sequentially heating and reducing said sulfides in a countercurrent flow of heating and reducing gases respectively in a reactor whereby the reaction products of the reducing gas and sulfides, together with liberated labile sulfur, are controllably combusted with oxygen to satisfy heat requirements of the thermal activation process and to convert sulfur values to SO.sub.2 gas. The activated sulfides are subjected to an acid leach in aqueous sulfuric acid for production of ferrous sulfate and evolution of H.sub.

Abstract: A hydrometallurgical method of recovering zinc, copper and cadmium from their ferrites so that the ferrites are treated under atmospheric conditions in sulphuric acid bearing solution in the presence of potassium-, sodium- or ammonium-ions, is disclosed, in which the treatment takes place in one stage under such conditions that the non-ferrous metals, zinc, copper and cadmium, contained in the ferrites are transferred as sulphates to the solution and the iron is converted in the same stage to a solid basic iron salt by adjusting the sulphuric acid or ferric sulphate addition to be equivalent with regard to the ferrite amount fed into this stage and by adjusting the temperature to 80.degree. - 105.degree.C, preferably to 95.degree. - 105.degree.

Abstract: A method is provided for separating nickel and cobalt from a cobalt-nickel precipitate, the cobalt being in the cobaltic state. The method comprises dissolving the precipitate in an ammonium sulfate solution containing NH.sub.3, acidifying the solution to a pH of about 1.5 to 3.0 and then cooling the solution to produce a nickel-ammonium sulfate precipitate highly enriched in nickel. The precipitate is separated from the solution and the solution passed through an ion exchange column selective to the removal of nickel, the solution remaining containing said cobalt substantially free of nickel, the cobalt solution being then sent to cobalt recovery.

Abstract: A method is provided for enriching nickel in a nickel-cobalt solution to a nickel-to-cobalt ratio of over 2000:1, wherein an aliquot portion of the solution is removed, the nickel precipitated from said aliquot portion in the nickelous state, the nickelous precipitate thereafter oxidized to the nickelic state and the oxidized nickel precipitate then mixed with the remaining nickel-cobalt solution to oxidize the cobalt therein to the cobaltic state which precipitates from the solution, thereby highly enriching the solution in nickel.