Abstract: Aqueous solutions containing lead, zinc and manganese are treated to recover these metals by sequential solvent extraction steps. Solvent extractants are selected to extract preferentially lead, then zinc and then manganese in that order. Any interfering metals are removed (as by ion exchange) before extraction. The loaded extractant phases are stripped with selected acids and lead, zinc and manganese each recovered from the strip solutions. Optionally calcium can be recovered when present. A preferred type of extractant (for lead especially) is substituted monothiophosphinic acids. A closed loop system is described which is advantageous with leachate from sulphide and carbonate ores.

Abstract: A method for the treatment of air pollution control (APC) residues comprising the steps of washing the residues at least one time in an alkaline solution maintained at a pH not lower than about 11.5, separating the alkaline washed residues from the alkaline solution. The present method further comprises an optional step of verifying whether the alkaline washed residues are substantially devoid of metal components. When the alkaline washed residues are not substantially devoid of metal components, the alkaline washed residues are washed at least one time in an acid solution maintained at a pH between about 2 and about 4.5 and the acid washed residues are separated from the acid solution so as to produce residues substantially devoid of metal components. The APC residues obtained in application of the methods according to the present invention constitute non-hazardous material/waste.

Abstract: This invention concerns catalysts comprising a molybdenum compound of formula I, II, III, IV or V I VqMoAyOz II NiMoxByOz′ III VNiwMoxCy′Oz″ IV CoNiwMoxDyOz′″ V VNiwCorMoxEyOz″″ wherein: A is at least one cation selected from the group consisting of cations of: Cr, Sb, Co, Ce and Pb; B is at least one cation selected from the group consisting of cations of: Sb, Al and W; C is at least one cation selected from the group consisting of cations of: Fe, Zn, Al, Sb, Bi, W, Li, Ba, Nb and Sn; D is at least one cation selected from the group consisting of cations of: Ba, Mn, Al, Sb, Sn, and W; E is at least one cation selected from the group consisting of cations of: Fe, Ca, Mn, Sr, Eu, La, Zr, Ga, Sn and Pb; q, r, w, x and y are each independently a number from 0.1 to 10 and y′ is a number from 0 to 10, z, z′, z″, z′″, and z″″ are determined using the amounts and oxidation states of all cations present in each formula.

Abstract: A method of treating metal-contaminated spent foundry sand, or other industrial waste, by combining the sand with a sulfite to produce insoluble metal sulfur oxide complexes that do not leach from the sand. The treated waste may also be processed to reduce “clumping,” thereby rendering the treated waste appropriate for use in another industrial process.

Abstract: The present invention provides a clathrate compound which can be used as a thermoelectric material, a hard material, or a semiconductor material. Silicon or carbon are formed into a clathrate lattice, and a clathrate compound is then formed in which specified doping atoms are encapsulated within the clathrate lattice, and a portion of the atoms of the clathrate lattice are substituted with specified substitution atoms. The clathrate lattice is, for example, a silicon clathrate 34 (Si34) mixed lattice of a Si20 cluster including a dodecahedron of Si atoms, and a Si28 cluster including a hexahedron of Si atoms. Suitable doping atoms are atoms from group 1A, group 2A, group 3A, group 1B, group 2B, group 3B, group 4A, group 5A, group 6A, and group 8, and suitable substitution atoms are atoms from group 1A, group 2A, group 3A, group 1B, group 2B, group 3B, group 5A, group 6A, group 7A, group 5B, group 6B, group 7B, and group 8 of the periodic table.

Abstract: A process for removing impurities contained in the crystal lattice of minerals, comprising the steps of forming a mixture of a mineral capable of structurally reorganizing its crystal lattice which contains an impurity in its crystal lattice and a halogen anion, and water; heating the mixture to the mineral's structural reorganization transition temperature; holding the mixture at the structural reorganization transition temperature for a sufficient period of time to allow the impurity to freely migrate from the lattice to combine with the halogen anion; and separating the combined impurity and anion from the mixture to render the mineral essentially free of the impurity. The process is applicable to numerous minerals and impurities, but is especially useful to remove arsenic from fluorspar. Numerous halogen anions can be employed, such as chlorides, fluorides, bromides and iodides, but the preferred halogen anion is a metal chloride such as calcium chloride.

Abstract: Disclosed is a positive active material for a rechargeable lithium battery. The positive active material includes at least one compound represented by formulas 1 to 4 andl a metal oxide or composite metal oxide layer formed on the compound.

Abstract: Positive electrode-active materials for use in lithium-ion and lithium-ion polymer batteries contain quaternary composite oxides of manganese, nickel, cobalt and aluminum where one of the four is present at levels of over 70 mol percent. The composite oxides can be lithiated to form positive electrode-active materials that are stable over at least ten charge/discharge cycles at voltage levels over 4.8 volts, and have capacities of over 200 mAh/g. Methods for producing the materials and electrochemical cells and batteries that include the materials are also provided.

Abstract: Disclosed is a positive active material of for a rechargeable lithium battery and a method of preparing the same.

Abstract: Disclosed is a method of preparing a positive active material for a rechargeable lithium battery. In this method, a lithium salt is reflux-reacted with a metal salt in a basic solution. The resulting positive active material is a compound represented by formulas 1 to 14. The positive active material has a spherical or spherical-like form, a diameter of 10 nm to 10 &mgr;m, and a surface area of 0.1 to 5 m2/g.

Abstract: The invention relates to a method for recovering non-ferrous metals, particularly nickel, cobalt, copper, zinc, manganese and magnesium, from materials containing said metals by converting said non-ferrous metals into sulphates by means of melt and melt coating sulphation, i.e. by a thermal treatment under oxidizing conditions within a temperature range of 400 to 800° C., during which a reaction mixture is formed containing at least one said non-ferrous metal, iron(III)sulphate and alkali metal sulphate, and appropriate reaction conditions are selected to substantially prevent iron(III)sulphate from thermally decomposing to hematite, and finally, said non-ferrous metals are recovered as metallic compounds. In the method of the invention, a process is formed around the melt and melt coating sulphation, which comprises nine steps.

Abstract: Solvent extraction of one or more metal ions from an aqueous solution in the presence of hydrocarbon-soluble aminomethylenephosphonic acid derivatives.

Abstract: An improved process for the beneficiation of mixtures of mineral particles (such as kaolin clays) containing minerals which chelate with hydroxamates. The use of a silicon-containing compound in combination with a hydroxamate results in a more effective separation of minerals which chelate with the hydroxamate.

Abstract: This invention relates to a new process for the extraction and elimination of deleterious material present in natural manganese dioxide (NMD), as well as in natural manganese dioxide obtained by such process. The process involves treating NMD with a HCl and water mixture in a reactor while stirring and heating the mixture. The heating temperature of the reactor is maintained in a predetermined range. The reactor is then fed with an amount of crushed NMD ore. A leaching reaction of said NMD ore with the HCl is produced by leaching for a period of time. Subsequently, the contents of the tank are filtered, washed and dried to recovery the concentrate of manganese dioxide substantially free of deleterious material.

Abstract: Process for removing manganese values from a solution of a water-immiscible hydrocarbon containing manganese values and a water-insoluble oxime extractant capable of extracting nickel values from aqueous ammoniacal solutions comprising the steps ofI) contacting the water-immiscible hydrocarbon solution with a finely divided active metal and an aqueous solution of a strong acid to decrease or complete remove the manganese values from said water-immiscible hydrocarbon solution; andII) separating the stripped hydrocarbon solution from the aqueous solution.The invention also relates to a method for the extraction of nickel from nickel-containing ores in which a content of manganese values is present in which the above process is used.

Abstract: The invention relates to a process for recovering the transition metal component of catalysts used in the hydroconversion of heavy hydrocarbonaceous materials. In accordance with the invention, a slurry of a transition metal catalyst and hydrocarbon is catalytically desulfurized resulting in a desulfurized product and a solid residue containing the transition metal. The transition metal may be recovered by coking the residue and then dividing the coker residue into two portions are combusted with the flue dust from the first combustion zone being conducted to the second combustion zone. The flue dust from the second combustion zone is treated with ammonia and ammonium carbonate in order to obtain ammonium molybdate.

Abstract: The invention relates to a process for recovering metals from used nickel/hydride storage batteries, in which storage battery scrap has been mechanically comminuted and divided into at least a coarse fraction and a fine fraction capable of being treated separately from one another. The process comprises the steps of digesting and dissolving the fine fraction with a mixture of sulfuric acid and hydrogen peroxide, performing a double sulfate precipitation of the rare earths by raising the pH, performing a precipitation of the iron and of the aluminum by further raising the pH, performing a solvent extraction of other metals to separate nickel and cobalt which remain in the aqueous phase from the other metals which are extracted into the organic phase. Optionally, the nickel and the cobalt can be separated from each other and, if desired, the mixed-metal rare earth component which has been recovered can be melted together with cobalt and nickel alloy for the fabrication of new batteries.

Abstract: A process for removing impurities contained in the crystal lattice of minerals, comprising the steps of forming a mixture of a mineral capable of structurally reorganizing its crystal lattice which contains an impurity in its crystal lattice and a halogen anion, and water; heating the mixture to the mineral's structural reorganization transition temperature; holding the mixture at the structural reorganization transition temperature for a sufficient period of time to allow the impurity to freely migrate from the lattice to combine with the halogen anion; and separating the combined impurity and anion from the mixture to render the mineral essentially free of the impurity. The process is applicable to numerous minerals and impurities, but is especially useful to remove arsenic from fluorspar. Numerous halogen anions can be employed, such as chlorides, fluorides, bromides and iodides, but the preferred halogen anion is a metal chloride such as calcium chloride.

Abstract: A method of removing HMO.sub.2.sup.- anions from an aqueous silicate solution comprising contacting the solution with a cationic ion exchange resin, where M is manganese, zinc, copper, nickel, or a mixture thereof. The method is particularly applicable to solutions of sodium silicate or potassium silicate.

Abstract: The invention relates to a method and apparatus for sintering finely divided material, containing manganese compounds with a particle size less than 6 mm and a high degree of oxidation, by means of some carbon-bearing material in a conveyor-type sintering apparatus (9) in an essentially continuous operation. According to the invention, through the material (8) to be sintered in the sintering apparatus (9), there is conducted hot gas (15, 18), which causes combustion reactions between the manganese compounds contained in the material and having a high degree of oxidation and the carbon contained in the burning material. Thus the sintering (18) is carried out essentially by means of the combustion heat released from the material (8). Moreover, the sintered material (8) is subjected to cooling (17) prior to removing the material from the sintering apparatus (9).

Abstract: Lithiated manganese oxides are synthesized using a novel two stage process. Using appropriate starting materials, lithiation is accomplished via low temperature ion exchange in aqueous warm salt solution. A drying stage follows which completes the synthesis. Materials suitable for use as cathodes in lithium ion rechargeable batteries have been prepared in this way. Other solid solution transition metal materials might also be prepared using a similar low temperature ion exchange process.

Abstract: An improved separation process for the continuous catalytic oxidation of aromatic alkyls for the production of aromatic carboxylic acids in a liquid solvent medium, wherein the reactor product stream is withdrawn from the oxidation process, then separated to produce a product containing stream, mother liquor stream and a catalyst containing purge stream which is then passed through a filtration system and series of sorption vessels to remove the oxidation catalyst and separate the impurities from the catalyst. The solvent is then separated from the reaction by-products by conventional distillation methods. The solvent is recycled to the process while the reaction by-product residue is disposed of by incineration. The oxidation catalyst is eluted from the ion exchange columns and returned to the process.

Abstract: A process is disclosed for the preparation of lithium secondary battery cathode active materials which are of the form Li.sub.y Mn.sub.2-z M.sub.2 O.sub.4 where M is selected from the group consisting of Co, Ni, Ti, V and Fe, y is in the range from 0 to 1.5 and z is in the range from 0 to 1. The process comprises forming a melt or saturated solution from manganese acetate, lithium hydroxide and water, keeping the melt/solution at a temperature in the range of 70 to 110.degree. C. for a period of from 10 minutes to 4 hours under stirring so as to form an essentially homogeneous material, and drying said material followed by calcination at a temperature in the range of 300 to 800.degree. C.

Abstract: The present invention relates to methods for digesting diphosphonic acid substituted cation exchange resins that have become loaded with actinides, rare earth metals, or heavy metals, in a way that allows for downstream chromatographic analysis of the adsorbed species without damage to or inadequate elution from the downstream chromatographic resins. The methods of the present invention involve contacting the loaded diphosphonic acid resin with concentrated oxidizing acid in a closed vessel, and irradiating this mixture with microwave radiation. This efficiently increases the temperature of the mixture to a level suitable for digestion of the resin without the use of dehydrating acids that can damage downstream analytical resins. In order to ensure more complete digestion, the irradiated mixture can be mixed with hydrogen peroxide or other oxidant, and reirradiated with microwave radiation.

Abstract: The present invention relates to a process for the production of pure ammonium metallates of the metals W, Mo, V, Cr and Re, wherein alkaline metal salt solutions are adjusted to a pH value in the range from 5 to 9 by reaction with CO.sub.2, these metal salt solutions are passed through an anion exchanger in carbonate form, wherein, in addition to the alkali metal carbonate solution, the metallate form of the ion exchanger is formed, the ion exchanger is then washed until free of alkali and is then eluted by means of aqueous ammonia to form ammonium metallate solutions and the anion exchanger in the OH form, wherein the anion exchanger is converted into the carbonate form by means of CO.sub.2 treatment and is recycled.

Abstract: A composition for extracting a transition metal which comprises as an active ingredient a cyclic phenol sulfide represented by the following formula (1): ##STR1## wherein X represents a hydrogen atom, a hydrocarbon group, an acyl group, a carboxyalkyl group, or a carbamoylalkyl group; Y represents a hydrocarbon group; Z represents a sulfide group, a sulfinyl group, or a sulfonyl group; and n is an integer of 4 to 8; and a method for extracting a transition metal using the composition

Abstract: A method for producing engineered materials from salt/polymer aqueous solutions in which an aqueous continuous phase having at least one metal cation salt is mixed with a hydrophilic organic polymeric disperse phase so as to form a metal cation/polymer gel. The metal cation/polymer gel is then treated to form a structural mass precursor, which structural mass precursor is heated, resulting in formation of a structural mass having predetermined characteristics based upon the intended application of the structural mass.

Abstract: The present invention relates to a method for the decomposition of superalloys and subsequent recovery of the metallic constituents.

Abstract: A novel process for making Li.sub.x Mn.sub.y O.sub.4 intercalation compounds, wherein 0<x.ltoreq.2 and 1.7.ltoreq.y.ltoreq.2, comprises the steps of: (1) synthesizing a lithiated manganese oxide precursor by reacting lithium hydroxide, manganese dioxide, and one or more polyhydric alcohols; and (2) heat-treating the lithiated manganese oxide precursor. The intercalation compounds are effectively employed as active components of positive electrodes in rechargeable lithiated intercalation battery cells.

Abstract: A process for producing nano size powders comprising the steps of mixing an aqueous continuous phase comprising at least one metal cation salt with a hydrophilic organic polymeric disperse phase, forming a metal cation salt/polymer gel, and heat treating the gel at a temperature sufficient to drive off water and organics within the gel, leaving as a residue a nanometer particle-size powder.

Abstract: Use of diethyl dodecylphosphonate (DEDP) for the extraction of acids and metal salts from aqueous solutions.

Abstract: A method for manufacturing Li.sub.2 Mn.sub.2 O.sub.4 which comprises the steps of providing LiMn.sub.2 O.sub.4 ; providing a lithium salt; forming a solution or suspension of the LiMn.sub.2 O.sub.4 and lithium salt in a liquid medium; and adding a reducing agent to the solution or suspension.

Abstract: A method of dissolving metal oxides using a mixture of a di- or polyphosphonic acid and a reductant wherein each is present in a sufficient amount to provide a synergistic effect with respect to the dissolution of metal oxides and optionally containing corrosion inhibitors and pH adjusting agents.

Abstract: Methods of recovering manganese in the form of manganese carbonate from ores containing manganese and iron while also removing substantially all of the iron contained in the sulfurous acid leach solution are disclosed.

Abstract: Manganese dry cells sorted out of used-up dry cells are crushed and sieved to obtain a mixture composed predominantly of anodic substances, which is in turn used for ferrite production. The invention is preferable for a saving of resources and preservation of the environment, and enables ferrites on a practical-enough level to be obtained.

Abstract: A process for producing intermediate grade manganese concentrate from low grade manganiferous ores is disclosed. A low grade manganiferous ore containing silicon, iron, between 1 and 20 per cent manganese and oxides of silicon, iron and manganese is first crushed to reduce the size of the manganiferous ore to a fraction of its original size. The crushed manganiferous ore is then heated to a temperature sufficient to chemically transform the manganese and iron in the manganiferous ore to an artificial magnetic, manganese-iron spinel. The heat treated manganiferous ore is cooled, preferably by air, and then beneficiated by further crushing and grinding to liberate the artificial manganese iron spinel from the silicon and other oxides within the ore. Finally, the artificial manganese-iron spinel is magnetically separated from the silicon and other oxides within the ore to increase the concentration of the manganese and thereby provide an intermediate grade manganese concentrate.

Abstract: Technetium is separated from radio-contaminated metal in a three-step process. The contaminated metal is dissolved in an acid solution; the technetium, present in the resultant solution as pertechnetate ions, is quantitatively reduced to its metallic state through a metal displacement (cementation) reaction with a base metal of lower reduction potential; and the desired metal is electrolytically recovered from the solution, substantially free from technetium contamination.

Abstract: A process for extracting technetium values from an aqueous alkaline solution containing at least one alkali metal hydroxide and at least one alkali metal nitrate, the at least one alkali metal nitrate having a concentration of from about 0.1 to 6 molar. The solution is contacted with a solvent consisting of a crown ether in a diluent for a period of time sufficient to selectively extract the technetium values from the aqueous alkaline solution. The solvent containing the technetium values is separated from the aqueous alkaline solution and the technetium values are stripped from the solvent.

Abstract: A process for treating an AB.sub.5 Ni--MH battery to recover purified positive and negative electrode components of the battery is disclosed. An AB.sub.5 Ni--MH battery is placed in a mineral acid leach solution to cause the positive and negative electrode components of the battery to separate. The positive and negative electrode components are maintained in the leach solution until the negative electrode component breaks down into its dissolved rare earth metal constituents and metallic solids. The metallic solids remaining from the negative electrode component and the positive electrode components are separated from the mineral acid leach solution and subjected to an elutriation process and thereafter to ball milling to obtain Ni rich powder and Fe. The mineral acid leach solution containing the completely dissolved rare earth metals is subjected to a phosphate precipitation process to recover La and Ce in precipitate, and then subjected to a second precipitation process to recover Ni, Co, Mn and Al.

Abstract: A process for producing manganese dioxide and zinc metal comprising the steps of:(1) reacting a mixture of zinc oxide and manganese oxide with an aqueous chloric acid solution wherein the chloric acid is in molar excess of the manganese oxide in a reaction zone to form a reaction mixture in the zone comprising chlorine gas, a solid phase containing manganese dioxide, and a liquid phase containing zinc oxide, chloric acid and water; the concentration of chloric acid in the liquid phase is greater than about 1% by weight of the liquid phase upon leaving the reaction zone;(2) separating the chlorine gas from the solid phase and the liquid phase;(3) separating the solid phase containing manganese dioxide from the liquid phase containing zinc ions, chlorate ions, chloric acid, and water thereby forming a separated solid phase and a separated liquid phase;(4) subjecting the separated liquid phase to electrolysis in an electrochemical cell, thereby producing zinc metal at the cathode and oxygen at the anode;(5) remo

Abstract: The invention relates to a process for the separation of at least one element such as Nb, Sb, Ce+Pr, actinides and elements from groups VIIb and VIII of the Periodic Classification of Elements from aqueous solutions resulting from the reprocessing of spent nuclear fuels.This process consists of contacting said aqueous solution with a solid resin based on a vinyl pyridine polymer or copolymer and separating from said solution the resin used for fixing said element or elements.The resin is in particular a poly(vinyl-4-pyridine) powder in crosslinked from and the separated elements are e.g. ruthenium, rhodium, palladium, technetium, manganese, cobalt, iron, nickel, cerium and praseodymium.

Abstract: Reduction roasting of manganese ore is the first step in the extraction of the metal, production of manganese based chemicals and benefaction of ferruginous manganese ores. In comparison to the conventional processes, the invented process replaces the expensive petroleum based reductant injected with air by cheap solid carbonaceous material and sealing of air entry. In the invented process the manganese ore, solid carbonaceous reductant and water are mixed. The mixture is formed into a bed on a grate. The top surface is ignited to incandescence while maintaining suction below the grate and then the top surface is sealed against entry of air while continuing the suction. The combustion of the solid reductant proceeds drawing the oxygen from the ore itself, resulting in high reduction. The product is cooled either by direct water quenching or by indirect means. The equipment employed is either a batch type pot or a continuous strand with sealing devices and material handling systems.

Abstract: Technetium-contaminated nickel is decontaminated by electrolytically dissolving nickel having a gross beta activity of at least about 74 Bq in a sulfuric acid solution having a pH between about 0.5 and 2.0. The applied voltage is from 2.0 v/cell to 5.0 v/cell for dissolving the nickel and contaminants while cathodically producing hydrogen gas. Technetium (+4) species in the acid solution is oxidized to the technetium (+7) species. The pH of the technetium-containing acid solution is adjusted to between 2.5 to 4.5. Particulates in the acid solution are filtered from the solution for reducing the gross beta activity of the acid solution to less than about 50 Bq/gm. Radioactive ions (including technetium complexes) are sorbed in an anionic exchanger and a cationic exchanger for reducing the gross beta activity of the acid solution to less than about 20 Bq/gm. After verifying the gross beta activity of the acid solution, the acid solution is either recycled or charged to a electrowinning step.

Abstract: A process is disclosed for the two-phase extraction of metal ions from phases containing solid metal oxides, which is characterized in that the solid metal oxides are brought into contact with a hydroxamic acid, known per se, dissolved in a hydrophobic organic solvent, the phases containing the solid metal oxides and the organic phase are intensively intermixed over a sufficient contact time, after phase-splitting, the organic phase is separated and the metal ions are re-extracted from the organic phase in a manner known per se and processed.The extracting agent used therein and the use of this extracting agent are also disclosed.

Abstract: A process for selective separation of germanium-68 from proton irradiated molybdenum targets is provided and includes dissolving the molybdenum target in a hydrogen peroxide solution to form a first ion-containing solution, contacting the first ion-containing solution with a cationic resin whereby ions selected from the group consisting of molybdenum, niobium, technetium, selenium, vanadium, arsenic, germanium, zirconium and rubidium remain in a second ion-containing solution while ions selected from the group consisting of rubidium, zinc, beryllium, cobalt, iron, manganese, chromium, strontium, yttrium and zirconium are selectively adsorbed by the first resin, adjusting the pH of the second ion-containing solution to within a range of from about 0.7 to about 3.

Abstract: A generator system for providing a carrier-free radioisotope in the form of an acid comprises a chromatography column in tandem fluid connection with an ion exchange column, the chromatography column containing a charge of a radioactive parent isotope. The chromatography column, charged with a parent isotope, is eluted with an alkali metal salt solution to generate the radioisotope in the form of an intermediate solution, which is passed through the ion-exchange column to convert the radioisotope to a carrier-free acid form.

Abstract: The transuranic (TRU) elements neptunium, plutonium and americium can be separated together with strontium from nitric acid waste solutions in a single process. An extractant solution of a crown ether and an alkyl(phenyl)-N,N-dialkylcarbanylmethylphosphine oxide in an appropriate diluent will extract the TRU's together with strontium, uranium and technetium. The TRU's and the strontium can then be selectively stripped from the extractant for disposal.

Abstract: Two alternate, mutually exclusive, methods of removing radio contaminants from metal are taught based respectively on electrowinning or electrorefining of the base metal. The alternative using electrorefining controls the anolyte oxidation potential to selectively reduce the technetium in the metallic feedstock solution from Tc(VII) to Tc(IV) forcing it to report to the anodic slimes preventing it from reporting to the cathodic metal product. This method eliminates the need for peripheral decontamination processes such as solvent extraction and/or ion exchange to remove the technetium prior to nickel electrorefining. The other alternative method combines solvent extraction with electrowinning. By oxidizing technetium to the heptavalent state and by using mixtures of tri-n-octyalphosphine oxide and di-2-ethyl phosphoric acid in aliphatic hydrocarbon carriers to extract the radio contaminants prior to electrowinning, the background metal may be recovered for beneficial reuse.

Abstract: Method is described for the low temperature preparation of the spinel LiMn.sub.2 O.sub.4 phase which is an intercalable compound of interest for use in lithium secondary batteries. This phase can be prepared in bulk or thick film form at temperatures less than 400.degree. C. using acetate precursors.

Abstract: A metal is dissolved by a method which comprises establishing contact of the metal with a quaternary ammonium compound and a halogenated hydrocarbon or with a quaternary ammonium compound, a halogenated hydrocarbon, and a polar solvent.