Kennecott Copper Corporation

Cabot Corporation

Other

The Standard Oil Company

Bp Corporation North America Inc.

Kennecott Utah Copper Corporation

Alkis S Rappas

J Paul Pemsler

Jameel Menashi

Donald A Douglas

Stephen C Paspek

John N Gerlach

David S Davies

Brett T Waterman

Lloyd R Allen

The present invention relates to a process for recovery of particulate calcium fluoride from a waste solution containing soluble fluoride. More specifically, the invention relates to a process for removal of soluble fluoride from and recovery of fluorspar-grade calcium fluoride from an aqueous waste solution using calcium sulfate to form the calcium fluoride. One aspect of the present invention is a process for removing soluble fluoride from a solution containing such soluble fluoride, the process including: (A) mixing the waste solution with an aqueous slurry containing seed calcium fluoride particles to form a first aqueous composition; (B) mixing the first aqueous composition with a calcium containing reagent to form a second aqueous composition; (C) advancing the second aqueous composition through a tubular reactor for an effective period of time and at a velocity sufficient to permit the soluble fluoride and the calcium containing reagent to react and attach to the seed particles of calcium fluoride, the seed particles of calcium fluoride thereby increasing in size to become enhanced particles; and (D) removing from the second aqueous composition a portion of the enhanced particles of calcium fluoride.

Process for removing soluble fluoride from a waste solution containing the same

The invention relates to a process for separating extractable organic material from a composition comprising organic material intermixed with solids and water. The composition is contacted with a solvent and a dehydrating agent. The dehydrating agent removes water, improves the solvent extraction, and aids in later separation of the solids from the solvent. The process additionally provides a means for removing cyanide compounds from the composition and fixating the metals against leaching.

Water managed solvent extraction process for the organic wastes

A process for the treatment of flue dust from copper and lead smelters includes the steps of subjecting a slurry (10) of water and flue dust to a first caustic leach (12) to form a first liquids soluble sulfate solution (14) and a first solids portion (15), subjecting the solids portion to a second caustic leach (16) to solubilize lead and arsenic in a second liquid portion (22) and, selectively extracting the arsenic from the second liquid portion by precipitation (23). A related process for the treatment of flue dust allows for the recovery of bismuth and includes the steps of separating (53) a slurry of water and flue dust into a first liquids (54) and first solids (63) portion, neutralizing (55) the first liquids portion to form a second liquids soluble sulfate solution (58) and a second solids portion (59), subjecting the first solids (63) portion to a first caustic leach (61) to produce a third liquids (66) and third solids portion (82), subjecting the third liquids portion (66) and the second solids portion (59) to a second caustic leach (60) to produce a fourth liquids (68) and fourth solids portion (91) and, selectively extracting arsenic from the fourth liquids portion (68) and bismuth from the third solids portion (82). A process for the recovery of soluble lead values from lead compounds includes the steps of subjecting a slurry (100) of the lead compound to a caustic leach (101) to solubilize the lead and oxidizing the lead in an electrolytic cell (38) to form lead oxide.

Processes for the treatment of smelter flue dust

The selective leaching of metal ions from various iron oxide and manganese oxide containing ores employs intermediary solutions. The leaching processes are based upon a redox acid leach step employing stabilized cuprous ions and, in one instance, a combination thereof with ferrous ions. Leaching is conducted at low temperatures, up to about 90.degree. C. and low pressures, up to about 1.5 MPa and at a pH of about 1.5 to 2.5. Nickel and cobalt recoveries from the ores, employing these processes, will usually equal or exceed 90 percent. The intermediary solutions comprise stabilized acidic cuprous ions Cu.sup.+ L wherein L is a stabilizing ligand selected from the group consisting of CO, XRCN and Cl.sup.-, X being --H or --OH and R being aliphatic having from one to about four carbon atoms. In at least one process, ferrous ions are introduced for a separate leaching step. Additional steps include regeneration of the lixiviant cuprous ion solutions and removing a portion of the copper ions from the copper ion solution before or after the step of regenerating. Several processes for the regeneration are possible employing quinolic compounds, H.sub.2, CO or syngas as reductants.

Processes relating to the extraction of metals from laterites and ocean

A pregnant liquor is mixed with an organic mixture comprised of an organic extracting agent and iso-butyl-heptyl ketone. Metallic values are absorbed from the pregnant liquor by the organic mixture. The metal-bearing organic mixture is then separated from the liquor and stripped of its metallic values.

Solvent extraction

Alloy scrap containing refractory metals such as chromium, molybdenum, tungsten, vanadium, niobium and tantalum and base metals such as nickel, cobalt, copper and iron are treated to partition the refractory metal values from the base metal values without an energy intensive remelting step. The scrap in finely divided form is calcined in the presence of an oxygen containing gas and a member of a certain group of alkali metal salts at a temperature in the range of 800.degree. C. to 1150.degree. C. for 1/4 hour to four hours. This treatment converts the refractory metals to alkali metal molybdates, tungstates, chromates, vanadates, niobates and tantalates and the base metals to oxides. The calcined product may then be water leached to produce a substantially base metal-free liquor rich in refractory metal values. Both the refractory and the base metal values may be subsequently recovered by conventional hydrometallurgical techniques.

Partitioning of refractory metals from oxidation resistant scrap alloy

Disclosed is a process for recovering chromium, vanadium, molybdenum, and tungsten from secondary resources such as alloy scrap comprising a refractory metal and base metals such as cobalt nickel, iron, and copper. The scrap is calcined with sodium carbonate in air to convert the refractory metal values to MoO.sub.4.sup..dbd., VO.sub.4.sup..tbd., WO.sub.4.sup..dbd., CrO.sub.4.sup..dbd., and the base metals to water insoluble oxides. A leach of the calcined materials produces a pregnant liquor rich in refractory metals which, after separation of the vanadium, molybdenum and tungsten values, is treated with CO, CHOO.sup.-, CH.sub.3 OH, or HCHO to reduce Cr.sup.+6 to Cr.sup.+3. The carbonate and bicarbonate salts produced as a byproduct of the reduction are recycled to the calcination stage. As a result of the V, W, and Mo partition, a mixed solid comprising CaO.multidot.nV.sub.2 O.sub.5, CaMoO.sub.4, and CaWO.sub.4 is produced. This is treated with carbonated water or formic acid to selectively dissolve vanadium values which are subsequently recovered by precipitation or extraction. The remaining mixed CaWO.sub.4 and CaMoO.sub.4 solid is treated with H.sub.2 O.sub.2 and sulfuric acid to reject a Mo and W-free CaSO.sub.4 precipitate, and to produce a concentrated solution of tungsten and molybdenum. The W values are selectively precipitated from this solution by decomposing the peroxy complexes. The process has the advantages that a wide variety of different feed materials can be treated, no energy intensive pyrometallurgy is involved, reagent consumption is minimized, and no aqueous effluents are produced.

Chromium recovery from scrap alloys

Disclosed is a process for recovering chromium, vanadium, molybdenum, and tungsten from secondary resources such as alloy scrap comprising a refractory metal and base metals such as cobalt, nickel, iron, and copper. The scrap is calcined with sodium carbonate in air to convert the refractory metal values to MoO.sub.4.sup.=, VO.sub.4.sup..ident., WO.sub.4.sup.=, and CrO.sub.4.sup.= and the base metals to water insoluble oxides. A leach of the calcined materials produces a pregnant liquor rich in refractory metals which, after separation of the vanadium, molybdenum and tungsten values, is treated with CO, CHOO.sup.- CH.sub.3 OH, or HCHO to reduce Cr.sup.+6 to CR.sup.+3. The carbonate and bicarbonate salts produced as a byproduct of the reduction are recycled to the calcination stage. As a result of the V, W, and Mo partition, a mixed solid comprising CaO.nV.sub.2 O.sub.5, CaMoO.sub.4, and CaWO.sub.4 is produced. This is treated with carbonated water or formic acid to selectively dissolve vanadium values which are subsequently recovered by precipitation or extraction. The remaining mixed CaWO.sub.4 and CaMoO.sub.4 solid is treated with H.sub.2 O.sub.2 and sulfuric acid to reject a Mo and W-free CaSO.sub.4 precipitate, and to produce a concentrated solution of tungsten and molybdenum. The W values are selectively precipitated from this solution by decomposing the peroxy complexes. The process has the advantages that a wide variety of different feed materials can be treated, no energy intensive pyrometallurgy is involved, reagent comsumption is minimized, and no aqueous effluents are produced.

Process for recovering chromium, vanadium, molybdenum and tungsten

Disclosed is a process for recovering chromium, vanadium, molybdenum, and tungsten from secondary resources such as alloy scrap comprising a refractory metal and base metals such as cobalt, nickel, iron, and copper. The scrap is calcined with sodium carbonate in air to convert the refractory metal values to MoO.sub.4.sup.=, VO.sub.4.sup..ident., WO.sub.4.sup.=, and CrO.sub.4.sup.= and the base metals to water insoluble oxides. A leach of the calcined materials produces a pregnant liquor rich in refractory metals which, after separation of the vanadium, molybdenum and tungsten values, is treated with CO, CHOO.sup.-, CH.sub.3 OH, or HCHO to reduce Cr.sup.+6 to Cr.sup.+3. The carbonate and bicarbonate salts produced as a byproduct of the reduction are recycled to the calcination stage. As a result of the V, W, and Mo partition, a mixed solid comprising CaO.nV.sub.2 O.sub.5, CaMoO.sub.4, and CaWO.sub.4 is produced. This is treated with carbonated water or formic acid to selectively dissolve vanadium values which are subsequently recovered by precipitation or extraction. The remaining mixed CaWO.sub.4 and CaMoO.sub.4 solid is treated with H.sub.2 O.sub.2 and sulfuric acid to reject a Mo and W-free CaSO.sub.4 precipitate, and to produce a concentrated solution of tungsten and molybdenum. The W values are selectively precipitated from this solution by decomposing the peroxy complexes. The process has the advantages that a wide variety of different feed materials can be treated, no energy intensive pyrometallurgy is involved, reagent consumption is minimized, and no aqueous effluents are produced.

Vanadium recovery from scrap alloys

Disclosed is a process for recovering chromium, vanadium, molybdenum, and tungsten from secondary resources such as alloy scrap comprising a refractory metal and base metals such as cobalt, nickel, iron, and copper. The scrap is calcined with sodium carbonate in air to convert the refractory metal values to MoO.sub.4.sup..dbd., VO.sub.4.sup..tbd., WO.sub.4.sup..dbd., and CrO.sub.4.sup..dbd. and the base metals to water insoluble oxides. A leach of the calcined materials produces a pregnant liquor rich in refractory metals which, after separation of the vanadium, molybdenum and tungsten values, is treated with CO, CHOO.sup.-, CH.sub.3 OH, or HCHO to reduce Cr.sup.+6 to Cr.sup.+3. The carbonate and bicarbonate salts produced as a byproduct of the reduction are recycled to the calcination stage. As a result of the V, W, and Mo partition, a mixed solid comprising CaO.nV.sub.2 O.sub.5, CaMoO.sub.4, and CaWO.sub.4 is produced. This is treated with carbonated water or formic acid to selectively dissolve vanadium values which are subsequently recovered by precipitation or extraction. The remaining mixed CaWO.sub.4 and CaMoO.sub.4 solid is treated with H.sub.2 O.sub.2 and sulfuric acid to reject a Mo and W-free CaSO.sub.4 precipitate, and to produce a concentrated solution of tungsten and molybdenum. The W values are selectively precipitated from this solution by decomposing the peroxy complexes. The process has the advantages that a wide variety of different feed materials can be treated, no energy intensive pyrometallurgy is involved, reagent consumption is minimized, and no aqueous effluents are produced.

Process for partitioning Mo and W from a mixed CaMoO.sub.4 -CaWO.sub.4

A novel class of extractants and a method of using the extractants in the hydrometallurgical recovery of nickel and cobalt metal. The extractants comprise a water immiscible organic solvent system containing solubilized mercaptide anions. In an important embodiment of the invention, the mercaptide anions are generated by solubilizing an alkali metal mercaptide in a polar organic solvent capable of solvating alkali metal ions. Alternatively, an organic solution of a mercaptan is exposed to an aqueous solution of NaOH or KOH to produce the mercaptide anion. The extractants are used by being contacted with cobalt, nickel, or cobalt and nickel pregnant aqueous solutions. On mixing, the cobalt and/or nickel values are taken up by the organic as cobalt or nickel mercaptides. These may then be stripped of cobalt and nickel by treatment with an aqueous alkaline solution and carbon monoxide.

Alkali metal mercaptide solvent extraction of cobalt, nickel

A novel class of extractants and a method of using the extractants in the hydrometallurgical recovery of nickel and cobalt metal. The extractants comprise a water immiscible organic solvent system containing solubilized mercaptide anion. In an important embodiment of the invention, the mercaptide anions are generated by adding compounds containing both a thiol group and an amine group such as aminoethanethiols or amides of thioglycolic acids to water immiscible organic solvents, preferably of polar character. These systems generate the required mercaptide anions by undergoing an internal acid dissociation. The extractants are used by being contacted with cobalt, nickel, or cobalt and nickel pregnant aqueous solutions. On mixing, the cobalt and/or nickel values are taken up by the organic as cobalt and nickel mercaptides. These may then be stripped of cobalt and nickel by treatment with an aqueous alkaline solution and carbon monoxide.

Amino-thiol nickel and cobalt solvent extraction

A novel class of extractants and a method of using the extractants in the hydrometallurgical recovery of nickel and cobalt metal. The extractants comprise a water immiscible organic solvent system containing solubilized mercaptide anions. In an important embodiment of the invention, the mercaptide ions are generated by adding a mercaptan to a mixed water immiscible solvent comprising a basic compound such as an amine, preferably a tertiary amine, and a polar component such as an alcohol, whereby the mercaptan undergoes acid dissociation. The extractants are used by being contacted with cobalt, nickel, or cobalt and nickel containing aqueous solutions. On mixing, the cobalt and/or nickel values are taken up by the organic as cobalt or nickel mercaptides. These may then be stripped of cobalt and nickel by treatment with an aqueous alkaline solution and carbon monoxide.

Nickel and cobalt solvent extraction with mercaptides

A novel process for recovering nickel metal from aqueous ammoniacal nickel solutions such as leach liquors at or close to ambient temperatures and pressures. The process comprises contacting the nickel solution with carbonyl ferrate ions such as HFe(CO).sub.4.sup.- or Fe(CO).sub.4.sup.-- in the presence of carbon monoxide to produce nickel carbonyl. The nickel carbonyl is collected as a gas, concentrated, and decomposed to produce nickel metal and carbon monoxide. The carbonyl ferrate ions may conveniently be produced by subjecting an iron pentacarbonyl solution to an aqueous alkaline solution containing potassium hydroxide or the like. The nickel depleted ammoniacal liquor is purged of iron resulting from the nickel carbonylation treatment by oxidizing the ferrous values to iron oxide and may thereafter be recycled to solubilize additional nickel values. The iron oxide in turn may be reduced to iron pentacarbonyl and treated with an aqueous alkaline solution for reuse in carbonylation of additional nickel values.

Nickel recovery employing carbonyl ferrates

A novel process for extracting, concentrating, and isolating nickel and cobalt from aqueous solution thereof. A cobalt and/or nickel bearing solution is contacted with an extractant comprising a substantially water immiscible organic solvent containing solubilized mercaptide anion to form water insoluble cobalt and nickel mercaptides in the organic phase. The organic phase is then separated from the raffinate and contacted with an alkaline solution and carbon monoxide to produce nickel and cobalt carbonyl compounds. Typically, the nickel carbonyl produced is gaseous Ni(CO).sub.4 which may be easily isolated by known methods from other components in the off-gas stream. Pure nickel metal is then obtained from the nickel tetracarbonyl by known methods. The cobalt carbonyl compound produced is typically water soluble carbonyl cobaltate ion, Co(CO).sub.4.sup.-, which may be oxidized to form water insoluble cobalt carbonyl compounds. The stripped extractant, the cobalt and nickel-free raffinate, and the carbon monoxide from the decomposition of carbonyl may be recycled.

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Bedford, MA, United States of America

Alkis S Rappas