Abstract: A method of decontaminating ground media. The method includes drilling an injection hole into ground media to a depth at or below where contaminants are also present, drilling one or more extraction holes into the ground media in close proximity to the injection hole, injecting a reagent into the injection hole, treating the ground media for a time sufficient to have a chelating agent chelate a metal present in the ground media, reacting the chelated metal with a peroxide to produce hydroxide ions, contacting the reagent with the ground media to decrease its permeability, contacting contaminants in the ground media with the hydroxide ions to convert the contaminants to environmentally safe compounds, increasing the pressure of the reagent into the ground media, further reducing the permeability of the ground media to release trapped contaminants, and transferring contaminants from the ground media to above a surface of the ground media.

Abstract: A method for preparing crystalline cobalt nitrate. The method includes: 1) calcining a spent Co/SiO2 catalyst, cooling the calcined material to room temperature, and grinding it to yield a powder; 2) heating the powder in a fluidized bed reactor; 3) adding the heated powder into excess dilute nitric acid solution and filtering to obtain a cobalt nitrate solution; 4) adjusting the pH value of the cobalt nitrate solution to 1.5, adding a preheated oxalic acid solution, adjusting a pH value of the resulting solution to 1.5, immediately filtering the resulting solution to yield a precipitate of cobalt oxalate, washing the precipitate of cobalt oxalate to yield a neutral filtrate; 5) drying the precipitate and calcining to yield cobalt oxide; 6) dissolving the cobalt oxide in nitric acid to yield a second cobalt nitrate solution; and 7) evaporating the second cobalt nitrate solution to obtain crystalline cobalt nitrate.

Abstract: A method for selectively processing a polymetallic oxide solution containing a plurality of base metals comprising at least one of: Cu, Co, Ni, Zn associated with iron, comprising acid leaching the solution; recovering a filtered leachate; oxidizing the leachate; and adjusting the pH of the leachate in presence of a complexing agent; wherein the acidic solution is one of: i) a hydrochloric acid solution and ii) a sulfuric acid solution at a pH lower than about 1.5, and the complexing agent is one of: i) ammonium chloride and ii) ammonium sulfate, the step of adjusting the pH comprising raising the pH to a range between about 2.5 and about 3.5.

Abstract: Zinc, nickel and iron can be recovered from spent brines and produced water using a method that includes admixing an aqueous fluid with hydrazine to form a hydrazine complex and then filtering or otherwise removing the hydrazine complex from the aqueous fluid. Once treated, the aqueous fluid can then be recycled or at be the subject to an easier disposal. The isolated metal hydrazine complex may be recycled or discarded.

Abstract: A process for the extraction of uranium compounds from wet-process phosphoric acid includes lowering the iron concentration of the wet-process phosphoric acid and reducing the valency of any remaining ferric iron in the wet-process phosphoric acid to ferrous iron, and then extracting uranium compounds from the wet-process phosphoric acid. The process can include separating a side stream from a feed stream of wet-process phosphoric acid, wherein the side stream has a greater concentration of the uranium compounds than the feed stream by filtration. Extracting uranium compounds from the wet-process phosphoric acid can be by ion exchange process or by solvent extraction.

Abstract: Methods are generally disclosed for synthesis of porous particles from a solution formed from a leaving agent, a surfactant, and a soluble metal salt in a solvent. The surfactant congregates to form a nanoparticle core such that the metal salt forms about the nanoparticle core to form a plurality of nanoparticles. The solution is heated such that the leaving agent forms gas bubbles in the solution, and the plurality of nanoparticles congregate about the gas bubbles to form a porous particle. The porous particles are also generally disclosed and can include a particle shell formed about a core to define an average diameter from about 0.5 ?m to about 50 ?m. The particle shell can be formed from a plurality of nanoparticles having an average diameter of from about 1 nm to about 50 nm and defined by a metal salt formed about a surfactant core.

Abstract: Process for the treatment of a lateritic nickel/cobalt ore consisting of a mixture (2) of limonite and saprolite, characterized in that: the mixture (2) in the presence of an iron-precipitating agent is made into a pulp (1), having a solids content of between 10 and 40% by weight; the pulp undergoes a leaching operation (4) with sulphuric acid (5), at a temperature between 70° C. and the boiling point and at atmospheric pressure; and a solid-liquid separation (8) is carried out so as to obtain an iron-containing solid residue (9) and a solution containing nickel and cobalt ions. Process for producing nickel and/or cobalt intermediate concentrates or commercial products using the above 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 extraction of uranium compounds from wet-process phosphoric acid includes lowering the iron concentration of the wet-process phosphoric acid and reducing the valency of any remaining ferric iron in the wet-process phosphoric acid to ferrous iron, and then extracting uranium compounds from the wet-process phosphoric acid. The process can include separating a side stream from a feed stream of wet-process phosphoric acid, wherein the side stream has a greater concentration of the uranium compounds than the feed stream by filtration. Extracting uranium compounds from the wet-process phosphoric acid can be by ion exchange process or by solvent extraction.

Abstract: Provided are processes for the production of titanium dioxide from ilmenite. In these processes, ilmenite is digested with aqueous ammonium hydrogen oxalate. Iron from the ilmenite precipitates as a hydrated iron oxalate and is removed by filtering, leaving a titanium-rich solution. The titanium-rich solution can be further processed to form titanium dioxide.

Abstract: Disclosed is a process for removing metals from waste, particularly electronic waste (or “e-waste”). The process generally includes the steps of dissolving at least some of the metals from the waste with nitric acid reagent and then causing at least some of the metals to precipitate as metal oxides and/or metal nitrates. NOx gases produced as by-product by the nitric acid dissolution of metallic components in the electronic waste are reused, in particular for generating permanganate when one of the metallic components comprises manganese.

Abstract: A process for recovering metals such as Ni, Co, Mn, Cu, Zn, among others, through precipitation as sulphides, enabling recovery of magnesium in the form of hydroxide, carbonate and oxide and providing recovery of sulphate as gypsum and ammonium sulphate. Liquid phase, after full treatment, comprises recovered water with a quality proper for total reuse in industrial process. This process of liquid and solid effluent treatment is provided with flexibility to process several types of effluents presenting wide variations in their chemical composition.

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 present invention relates to a process for the removal of metal catalyst degradation products from a bleed stream of a catalytic chemical reaction process, wherein the catalyst is based on a metal selected from those in group VIII of the periodic table, chromium, copper, molybdenum, tungsten, rhenium, vanadium, titanium and zirconium, said process comprising treatment of the bleed stream with an alkali metal carbonate or ammonium carbonate source to form a solid complex or an aqueous solution of said solid complex, and removal of the solid complex or the aqueous solution of said solid complex from the bleed stream.

Abstract: Provided are processes for the production of titanium dioxide from ilmenite. In these processes, ilmenite is digested with aqueous trimethylammonium hydrogen oxalate. Iron from the ilmenite precipitates as a hydrated iron oxalate and is removed by filtering, leaving a titanium-rich solution. The titanium-rich solution can be further processed to form titanium dioxide.

Abstract: A process for the recovery of nickel and/or cobalt from an impure nickel, cobalt or mixed nickel/cobalt material including the steps of: a) providing a nickel, cobalt or mixed nickel/cobalt material; and b) contacting the nickel, cobalt or mixed nickel/cobalt material with a feed ammoniacal ammonium carbonate solution and a reductant in a leach step.

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: An atmospheric leach process in the recovery of nickel and cobalt from lateritic ores, said processing including the steps of: a) separating the lateritic ore into a low magnesium containing ore fraction, and a high magnesium containing ore fraction by selective mining or post mining classification; b) separately slurrying the separated ore fractions; c) leaching the low magnesium containing ore fraction with concentrated sulphuric acid as a primary leach step; and d) introducing the high magnesium content ore slurry following substantial completion of the primary leach step and precipitating iron as goethite or another low sulphate containing form of iron oxide or iron hydroxide, wherein sulphuric acid released during iron precipitation is used to leach the high magnesium ore fraction as a secondary leach 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: The invention provides an effective and efficient method of making a hexammine cobaltic salt, such as hexammine cobaltic nitrate, in a consistent fashion through the control of one or more selected parameters of manufacture. Specific parameters considered and evaluated as a part of the invention included: order of addition of reactants, reaction temperature, oxidation, air or oxidant flow, catalyst content, and amount of ammonia.

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: A process for producing potassium nitrate and other metal nitrates from the chlorides, sulfates, oxides of these metals. The process uses nitrogen dioxide as a true fluidizing medium in shallow beds of the aforementioned solids at moderately elevated temperatures in a continuous counter current process to convert the metal chlorides, sulfates, and oxides, into metal nitrates and effluent gas and water vapor. The process may be carried out in a series of true fluidized beds arranged in a vertical configuration so that the solids flow downward due to the fluidized process and the nitrogen dioxide gas flows counter currently in an upward direction producing pure metal nitrates at the bottom and nitrosyl chloride gas and/or water vapor at the top.

Abstract: A method of decontaminating soil and ground water containing organic contaminants and divalent metal compounds. It comprises the steps of first treating such soils and ground water with an effective amount an aqueous solution containing a peroxide and a water soluble chelating agent for a time sufficient to have the water soluble chelating agent chelate at least one of the divalent metals of the divalent metal compounds present in the soil and ground water. Next, the chelated metals are brought into contact with the peroxide to catalytically convert the peroxide to an oxidizing agent. Finally, the last step is contacting the organic contaminants in the soil and ground water with the oxidizing agent to oxidize the organic contaminants to environmentally safe, non-toxic compounds.

Abstract: A process is provided for the leaching of both the “limonite” (Fe approx. ≧25% and Mg approx. ≧6%) and “saprolite” (Fe approx. ≦20% and Mg approx. ≧10%) fractions of typical nickel and cobalt bearing laterite ore. The low magnesium fraction of the laterite ore is leached with sulfuric acid at high pressure and temperature to solubilize the metal values while precipitating most of the solubilized iron as hematite or other iron compounds and a portion of the dissolved aluminum as alunite or other aluminum compounds. After reducing the pressure of the leach slurry to approximately atmospheric pressure, the pregnant leach slurry or solution is contacted with the high magnesium fraction of the ore to solubilize most of the nickel contained in the high-magnesium ore fraction while dissolving only a small portion of the iron content of the high magnesium ore fraction.

Abstract: The present invention provides both reagents and a process for removing heavy metals from a caustic fluid stream by the addition of reagents which are not corrosive or deleterious. Specifically, the present invention is directed to removing heavy metals from a Bayer liquor in an aluminum processing plant. The reagents, dithiocarbamate and dithocarbonate groups, are added individually or in combination thereof to the Bayer liquor for the removal of heavy metals, such as zinc. The reagents form a complex with the heavy metal for the precipitation of the metal from the fluid stream. Once a complex is formed, the Bayer liquor is held in a quiescent state for a period of time sufficient for settling out of solution the precipitate. After settling out of solution, the precipitate is separated and removed and the Bayer liquor is then further processed into alumina.

Abstract: A magnetic material made up of an assembly of particles substantially consisting of an &agr;″-Fe16N2 crystal having a body-centered tetragonal system (bct). The magnetic material has a high saturated magnetic flux density and is directly synthesized by reacting fine particles of &agr;-Fe and a nitrogen-containing gas at a temperature of 200° C. or lower. By the synthesis of this invention, &agr;″-Fe16N2, which is a metastable compound conventionally deposited accompanied with phase transformation of crystallization from a martensite phase of &agr;′-Fe(N), is obtained as an isolated bulk substance in a single phase.

Abstract: A process is provided for leaching nickeliferous laterite ores by hydrometallurgical methods at temperatures below the boiling point of the pulp and at atmospheric pressure from which high overall nickel and cobalt extractions are obtained. The high iron fraction of the laterite, referred to as limonite, is first contacted with a concentrated mineral acid to partially or completely dissolve the iron and nickel in solution. During this process, 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 will allow the 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) dissolving nickel into solution.

Abstract: A treatment of metallurgical dust and recovery of valuable chemical commodities, comprising the steps of: leaching salts from the dust with water to create a washed EAF dust; reacting the washed EAF dust in a nitric acid solution resulting in a nearly complete dissolution of the zinc, cadmium, copper, magnesium, calcium, manganese and lead from a filtrate; removing iron from the filtrate by raising pH in the system with basic zinc carbonate; removing cadmium, copper and lead in an electrolytic cell, where copper and cadmium are collected at the cathode, and lead is collected at the anode; evaporating and decomposing the filtrate to obtain metal oxides and anhydrous calcium nitrate; leaching the solid residue with water to separate calcium nitrate in a marketable form; removing the zinc from the magnesium and manganese by leaching the residue with an amine solution; stripping the filtrate of ammonium carbonate to yield zinc precipitated as a zinc oxycarbonate; dividing the zinc oxycarbonate into a first stream

Abstract: An apparatus for cleaning the surface of teeth in a human mouth having a flexible, resilient central flossing filament and a plurality of flexible side flossing filaments fixedly attached to a central filament intermediate portion. The central filament intermediate and free end portions, with the side flossing filaments attached thereto, are sized to be received between adjacent teeth without traversing any contact areas between the adjacent teeth from at least the front of the mouth. The central filament has sufficient flexibility and resiliency to effect a first flossing action between the adjacent teeth by imparting a first flossing motion to the central filament, and the side filaments have sufficient flexibility to effect a second flossing action between the adjacent teeth and at the forward and rearward surfaces thereof to impart a second flossing motion to the side filaments.

Abstract: A corrosion inhibitor pigment composition is based a solid solution of (Ni.sup.2+ +Co.sup.2+)-bis-hydrogen cyanamide.

Abstract: A method of preparing a (Me)bis-hydrogen cyanamide composition with enhanced corrosion preventive activity, wherein Me is a divalent metal selected from the group consisting of nickel and cobalt or mixtures thereof. The method includes precipitating Ni(OH).sub.2 or Co(OH).sub.2 or mixtures thereof, in situ in a liquid reaction medium, containing a soluble cobalt or nickel salt and sodium hydroxide and a stoichiometric excess of H.sub.2 NCN and immediately reacting the resultant precipitate with H.sub.2 NCN. Precipitation of coprecipitated pigment compositions including the aforementioned derivatives and zinc cyanamide is also disclosed.

Abstract: Metal complexes having high bulk density and a process for the production of the same without the generation of heavy metal-contaminated effluents are disclosed. Solid complexes of EDTANaFe and EDTAKFe having high bulk densities are formed by reaction with mixed metal solutions containing low chromium levels, followed by total drying of the resulting mixture in the same processing equipment without the prior separation of the sulfate salts formed. The amounts of the various metals in any given formulation can be preselected.

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: Fe(III) complexes having high bulk density and a process for the production of the same without the generation of heavy metal-contaminated effluents are disclosed. Solid complexes of EDTANaFe and EDTAKFe having high bulk densities are formed by reaction with ferric sulfate containing low chromium levels, followed by total drying of the resulting mixture in the same processing equipment without the prior separation of the sulfate salts formed.

Abstract: A liquid oxidizing system has a closed circuit in which a liquid containing matter to be oxidized is circulated. The circuit is provided with an ejector for forming a jet stream of the liquid into which oxygen, or both oxygen and an oxidizing catalyst are supplied. The oxygen (and the catalyst) rapidly contacts the matter to be oxidized in the jet stream and oxidizes it. The system is not only applicable to the treatment of waste water, such as from factories, but also useful for making a product by oxidizing a liquid, e.g. iron polysulfate which is a good coagulant.

Abstract: A method for treating cyanide-contaminated water in order to remove dissolved (e.g. free) cyanide (HCN and/or CN.sup.-) therefrom. Cyanide-contaminated water is a significant problem in the gold processing industry wherein cyanide compounds are used to remove gold from ore. The remaining cyanide solution after gold extraction is treated to reduce free cyanide levels therein by combining the solution with a crystalline waste by-product of the metal galvanizing industry having the following formula: (Fe.multidot.Zn)SO.sub.4 .multidot.7H.sub.2 O. This material preferably has a zinc content of about 1-14% by weight, and is added to the water in an amount equal to about 1-5 pounds per ton of ore being processed. As a result, a stable, solid, non-toxic complex is produced from the toxic free cyanide materials. This is accomplished without the generation of harmful acids, heavy metals, excessive iron levels or other undesired by-products.

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: A process for the separation and recovery of nickel from an ammoniacal ammonium carbonate liquor containing nickel II ions and cobalt III ions by liquid-liquid extraction where ammoniacal ammonium carbonate solutions are the only aqueous phases involved in the process. The process includes the successive steps of: (a) oxidizing the majority of any cobalt II ammines in the ammoniacal liquid to cobalt III; (b) extracting nickel from the ammoniacal liquor with an organic reagent, which reagent may also contain a suitable modifying reagent, to form a nickel loaded organic phase and an ammoniacal ammonium carbonate phase containing cobalt; (c) stripping the nickel loaded organic phase characterized by contacting the organic phase with an ammoniacal ammonium carbonate solution to form a nickel loaded aqueous strip liquor.

Abstract: Fe(III) complexes having high bulk density and a process for the production of the same without the generation of heavy metal-contaminated effluents are disclosed. Solid complexes of EDTANaFe and EDTAKFe having high bulk densities are formed by reaction with ferric sulfate containing low chromium levels, followed by total drying of the resulting mixture in the same processing equipment without the prior separation of the sulfate salts formed.

Abstract: A process is provided for selectively separating oxygen from an oxygen-containing fluid stream by bringing said fluid stream into contact with a high capacity solid state cyanocobaltate complex in a non-aluminosilicate environment represented by the chemical formula:A.sub.x/z.sup.z+ [Co(CN).sub.n ].sup.x- .multidot.pSwhere:A is an alkali, alkaline earth, transition, or Group 12 metal atom;z is 1, 2 or 3;n is any number from 3 to 5;x is n-2;p is any number from greater than zero to 6; andS is a ligand which is capable of coordinating with A.sup.z+, Co or both.These complexes chemically bind oxygen to form novel oxygen adducts, thereby selectively removing oxygen from the fluid stream. The bound oxygen may be recovered by increasing the temperature or by reducing the partial pressure of O.sub.2 above the adduct.

Abstract: A method for reducing impurity levels of calcium, magnesium and/or silicon in hexammine cobalt halide compounds involves the addition of ferric ions and, optionally, soluble fluorides to an aqueous hexammine cobalt (III) chloride solution having a pH of at least 9. Insoluble compounds of magnesium fluoride, calcium fluoride, and/or ferric hydroxide and silicon coprecipitates are removed from the solution by filtration.

Abstract: A process is provided for recovering cobalt values from a cobalt-N-acetyliminodiacetic acid complex by dissolving the complex in an aqueous solution of a strong acidic solution, extracting the acid solution with a hydrocarbon solvent containing a trialkylamine to transfer the cobalt from the aqueous solution into the hydrocarbon solvent, stripping the cobalt from the hydrocarbon solvent with water, and precipitating the cobalt from the stripping water by using a strong alkali.

Abstract: In a method of preparing high-purity manganese compounds, wherein the method comprises adding a member selected from ferromanganese and metallic manganeses to an aqueous electrolyte-containing solution, dissolving said member while stirring and maintaining a pH of 2 to 9, and then removing insolubles by filtration and recovering solubles by precipitation, heavy metal elements as well as non-metllic elements, such as P, Si, etc. can be removed efficiently, and high-purity manganese compounds of stable quality can be prepared.

Abstract: Refining of either niobium hydroxide or tantalum hydroxide containing transition metals as impurities is accomplished easily and economically by dissolving the metal hydroxide in an aqueous solution of either hydrofluoric acid or oxalic acid, adjusting the pH of the solution to 1 to 4 and adding ammonium pyrrolidinedithiocarbamate (APDC) to the solution while maintaining the temperature of the solution below 60.degree. C. The addition of APDC causes the transition metals to simultaneously precipitate as coordination compounds. The minimum amount of APDC is 0.05 wt % of Nb.sub.2 O.sub.5 or Ta.sub.2 O.sub.5 that can be formed from Nb or Ta contained in the solution. After the treatment with APDC the pH of the solution is raised to 6 or above to precipitate the refined metal hydroxide.

Abstract: A method for producing titanium fluoride comprises: a dissolution process, wherein iron-containing titanium material is dissolved in solutions containing hydrofluoric acid, fluoride solutions being produced; a first crystallization and separation process, wherein ferric fluoride is crystallized and ferric fluoride crystals thus obtained are separated from the fluoride solutions by cooling the fluoride solutions, crude titanium fluoride solutions being produced; a second crystallization and separation process, wherein a mixed salt of (NH.sub.4).sub.2 TiF.sub.6 and (NH).sub.3 FeF.sub.6 is crystallized and separated by mixing ammonium fluoride solutions with the crude titanium fluoride solutions to obtain a mixture and concentrating the mixture; a first pyrolysis process, wherein the ammonium fluoride salt is pyrolyzed at a temperature of from 300.degree. to 800.degree. C. in a stream of dry gas after having dried the ammonium fluoride, solid ferric fluoride (FeF.sub.3) and gaseous TF.sub.4, HF and NH.sub.

Abstract: This invention is directed to an improved process for leach treating gold and silver bearing pyritic and arsenopyritic concentrates and ores. More particularly, the improved process avoids the necessity of adding recycled neutralized solution to the leach solution, thereby alleviating difficulties in maintaining acid levels in the leach solution, and provides for bleeding solutions containing dissolved arsenic, iron and sulphate from the process without the loss oxidized nitrogen species. The process can be carried out in one or more tubular reactors. The process for recovering valuable metals from pyritic and arsenopyritic concentrates and ores involves decomposing the arsenopyrite or pyrite concentrates and ores in acidic solution in a common volume space which contains a gas phase and a liquid slurry (which comprises a liquid phase and a solid phase) through the action of higher valence oxidized nitrogen species in which the nitrogen has a valence of at least plus 3.

Abstract: A metal stripping system and an operation process therefor which includes the following elements and steps. A main part of this system is a crystallization apparatus for metal stripping comprising a mixing zone of organic solvent and fluoride series stripping solution, a settling zone for organic solvent, a settling zone for stripping solution, a separation zone for fluorinated metal complex crystal and a stripping solution cooling zone. In the operation of the system wherein the organic solvent containing extracted metal ions is contacted with the fluoride series stripping solution to deposit the fluorinated metal complex crystal and then the crystal is recovered as metal or metal oxide, the stripping solution is circularly used by supplying NH.sub.4 HF.sub.