WO1984000562A1 - Method of recovering metals from metal containing materials - Google Patents
Method of recovering metals from metal containing materials Download PDFInfo
- Publication number
- WO1984000562A1 WO1984000562A1 PCT/US1982/001059 US8201059W WO8400562A1 WO 1984000562 A1 WO1984000562 A1 WO 1984000562A1 US 8201059 W US8201059 W US 8201059W WO 8400562 A1 WO8400562 A1 WO 8400562A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- metal
- reagent
- group
- reaction
- sodium
- Prior art date
Links
- 229910052751 metal Inorganic materials 0.000 title claims abstract description 47
- 239000002184 metal Substances 0.000 title claims abstract description 47
- 238000000034 method Methods 0.000 title claims abstract description 27
- 239000000463 material Substances 0.000 title claims abstract description 11
- 150000002739 metals Chemical class 0.000 title abstract description 16
- 239000003153 chemical reaction reagent Substances 0.000 claims abstract description 29
- 238000006243 chemical reaction Methods 0.000 claims abstract description 25
- 229910052783 alkali metal Inorganic materials 0.000 claims abstract description 17
- 150000001340 alkali metals Chemical class 0.000 claims abstract description 17
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 8
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 8
- 239000001301 oxygen Substances 0.000 claims abstract description 8
- 150000008044 alkali metal hydroxides Chemical class 0.000 claims abstract description 7
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 claims description 16
- 239000011734 sodium Substances 0.000 claims description 16
- 229910052708 sodium Inorganic materials 0.000 claims description 14
- 238000000354 decomposition reaction Methods 0.000 claims description 9
- 239000001257 hydrogen Substances 0.000 claims description 8
- 229910052739 hydrogen Inorganic materials 0.000 claims description 8
- 229920001223 polyethylene glycol Polymers 0.000 claims description 8
- 239000000376 reactant Substances 0.000 claims description 8
- 239000002202 Polyethylene glycol Substances 0.000 claims description 6
- KKEBXNMGHUCPEZ-UHFFFAOYSA-N 4-phenyl-1-(2-sulfanylethyl)imidazolidin-2-one Chemical compound N1C(=O)N(CCS)CC1C1=CC=CC=C1 KKEBXNMGHUCPEZ-UHFFFAOYSA-N 0.000 claims description 5
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 5
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 claims description 5
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 claims description 5
- 229910052744 lithium Inorganic materials 0.000 claims description 5
- 239000011591 potassium Substances 0.000 claims description 5
- 229910052700 potassium Inorganic materials 0.000 claims description 5
- 125000000217 alkyl group Chemical group 0.000 claims description 4
- 239000002904 solvent Substances 0.000 claims description 4
- 125000004432 carbon atom Chemical group C* 0.000 claims description 3
- 230000000737 periodic effect Effects 0.000 claims description 3
- 229910000497 Amalgam Inorganic materials 0.000 claims description 2
- 150000001298 alcohols Chemical class 0.000 claims description 2
- 150000001338 aliphatic hydrocarbons Chemical class 0.000 claims description 2
- 150000004945 aromatic hydrocarbons Chemical class 0.000 claims description 2
- 150000002431 hydrogen Chemical class 0.000 claims description 2
- 125000004435 hydrogen atom Chemical group [H]* 0.000 claims description 2
- 150000002576 ketones Chemical class 0.000 claims description 2
- 125000003107 substituted aryl group Chemical group 0.000 claims description 2
- 125000005346 substituted cycloalkyl group Chemical group 0.000 claims description 2
- 229920000151 polyglycol Polymers 0.000 abstract description 6
- 239000010695 polyglycol Substances 0.000 abstract description 6
- 230000008569 process Effects 0.000 abstract description 5
- 239000002699 waste material Substances 0.000 abstract description 4
- 150000001346 alkyl aryl ethers Chemical class 0.000 abstract 1
- 238000011084 recovery Methods 0.000 description 10
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 9
- -1 alkyl radical Chemical class 0.000 description 7
- 239000011541 reaction mixture Substances 0.000 description 7
- 239000007788 liquid Substances 0.000 description 6
- 230000001603 reducing effect Effects 0.000 description 5
- 230000015572 biosynthetic process Effects 0.000 description 4
- 150000001875 compounds Chemical class 0.000 description 4
- 238000010438 heat treatment Methods 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- 238000003756 stirring Methods 0.000 description 4
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- 229920002565 Polyethylene Glycol 400 Polymers 0.000 description 3
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 3
- KEAYESYHFKHZAL-UHFFFAOYSA-N Sodium Chemical compound [Na] KEAYESYHFKHZAL-UHFFFAOYSA-N 0.000 description 3
- 230000008859 change Effects 0.000 description 3
- 239000010941 cobalt Substances 0.000 description 3
- 229910017052 cobalt Inorganic materials 0.000 description 3
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 3
- MTHSVFCYNBDYFN-UHFFFAOYSA-N diethylene glycol Chemical compound OCCOCCO MTHSVFCYNBDYFN-UHFFFAOYSA-N 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- 239000007787 solid Substances 0.000 description 3
- 239000000243 solution Substances 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 description 2
- 229910001854 alkali hydroxide Inorganic materials 0.000 description 2
- 125000000484 butyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 2
- ZUOUZKKEUPVFJK-UHFFFAOYSA-N diphenyl Chemical compound C1=CC=CC=C1C1=CC=CC=C1 ZUOUZKKEUPVFJK-UHFFFAOYSA-N 0.000 description 2
- 125000001495 ethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 description 2
- 150000002334 glycols Chemical class 0.000 description 2
- 239000010931 gold Substances 0.000 description 2
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 2
- 125000000959 isobutyl group Chemical group [H]C([H])([H])C([H])(C([H])([H])[H])C([H])([H])* 0.000 description 2
- 238000003760 magnetic stirring Methods 0.000 description 2
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 2
- 229920000642 polymer Polymers 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 125000001436 propyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])[H] 0.000 description 2
- 150000003254 radicals Chemical class 0.000 description 2
- 230000009257 reactivity Effects 0.000 description 2
- 238000006722 reduction reaction Methods 0.000 description 2
- 229910052709 silver Inorganic materials 0.000 description 2
- 239000004332 silver Substances 0.000 description 2
- 229910001948 sodium oxide Inorganic materials 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- SBASXUCJHJRPEV-UHFFFAOYSA-N 2-(2-methoxyethoxy)ethanol Chemical compound COCCOCCO SBASXUCJHJRPEV-UHFFFAOYSA-N 0.000 description 1
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 1
- 239000004721 Polyphenylene oxide Substances 0.000 description 1
- KJTLSVCANCCWHF-UHFFFAOYSA-N Ruthenium Chemical compound [Ru] KJTLSVCANCCWHF-UHFFFAOYSA-N 0.000 description 1
- BUGBHKTXTAQXES-UHFFFAOYSA-N Selenium Chemical compound [Se] BUGBHKTXTAQXES-UHFFFAOYSA-N 0.000 description 1
- 229910021607 Silver chloride Inorganic materials 0.000 description 1
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 1
- 238000007792 addition Methods 0.000 description 1
- 125000003545 alkoxy group Chemical group 0.000 description 1
- 125000003368 amide group Chemical group 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 150000005840 aryl radicals Chemical class 0.000 description 1
- 125000004429 atom Chemical group 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 125000001797 benzyl group Chemical group [H]C1=C([H])C([H])=C(C([H])=C1[H])C([H])([H])* 0.000 description 1
- 229910052790 beryllium Inorganic materials 0.000 description 1
- ATBAMAFKBVZNFJ-UHFFFAOYSA-N beryllium atom Chemical compound [Be] ATBAMAFKBVZNFJ-UHFFFAOYSA-N 0.000 description 1
- 235000010290 biphenyl Nutrition 0.000 description 1
- 239000004305 biphenyl Substances 0.000 description 1
- 125000001246 bromo group Chemical group Br* 0.000 description 1
- 229910052793 cadmium Inorganic materials 0.000 description 1
- BDOSMKKIYDKNTQ-UHFFFAOYSA-N cadmium atom Chemical compound [Cd] BDOSMKKIYDKNTQ-UHFFFAOYSA-N 0.000 description 1
- 229910052792 caesium Inorganic materials 0.000 description 1
- TVFDJXOCXUVLDH-UHFFFAOYSA-N caesium atom Chemical compound [Cs] TVFDJXOCXUVLDH-UHFFFAOYSA-N 0.000 description 1
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 1
- 238000005119 centrifugation Methods 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 125000001309 chloro group Chemical group Cl* 0.000 description 1
- 229910000428 cobalt oxide Inorganic materials 0.000 description 1
- IVMYJDGYRUAWML-UHFFFAOYSA-N cobalt(ii) oxide Chemical compound [Co]=O IVMYJDGYRUAWML-UHFFFAOYSA-N 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 125000000582 cycloheptyl group Chemical group [H]C1([H])C([H])([H])C([H])([H])C([H])([H])C([H])(*)C([H])([H])C1([H])[H] 0.000 description 1
- 125000000113 cyclohexyl group Chemical group [H]C1([H])C([H])([H])C([H])([H])C([H])(*)C([H])([H])C1([H])[H] 0.000 description 1
- 125000000640 cyclooctyl group Chemical group [H]C1([H])C([H])([H])C([H])([H])C([H])([H])C([H])(*)C([H])([H])C([H])([H])C1([H])[H] 0.000 description 1
- 125000001511 cyclopentyl group Chemical group [H]C1([H])C([H])([H])C([H])([H])C([H])(*)C1([H])[H] 0.000 description 1
- 238000007865 diluting Methods 0.000 description 1
- 230000003292 diminished effect Effects 0.000 description 1
- 230000003467 diminishing effect Effects 0.000 description 1
- 230000008034 disappearance Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 150000002170 ethers Chemical class 0.000 description 1
- LYCAIKOWRPUZTN-UHFFFAOYSA-N ethylene glycol Natural products OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 1
- 230000007717 exclusion Effects 0.000 description 1
- 239000002360 explosive Substances 0.000 description 1
- 230000005294 ferromagnetic effect Effects 0.000 description 1
- 230000014509 gene expression Effects 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 125000005843 halogen group Chemical group 0.000 description 1
- 125000004051 hexyl group Chemical group [H]C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])* 0.000 description 1
- 150000004679 hydroxides Chemical class 0.000 description 1
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Natural products OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 description 1
- 229910052741 iridium Inorganic materials 0.000 description 1
- GKOZUEZYRPOHIO-UHFFFAOYSA-N iridium atom Chemical compound [Ir] GKOZUEZYRPOHIO-UHFFFAOYSA-N 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000003446 ligand Substances 0.000 description 1
- 230000005291 magnetic effect Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 150000002736 metal compounds Chemical class 0.000 description 1
- 229910000000 metal hydroxide Inorganic materials 0.000 description 1
- 150000004692 metal hydroxides Chemical class 0.000 description 1
- 239000013528 metallic particle Substances 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 239000011733 molybdenum Substances 0.000 description 1
- 125000001624 naphthyl group Chemical group 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 229910052762 osmium Inorganic materials 0.000 description 1
- SYQBFIAQOQZEGI-UHFFFAOYSA-N osmium atom Chemical compound [Os] SYQBFIAQOQZEGI-UHFFFAOYSA-N 0.000 description 1
- 239000007800 oxidant agent Substances 0.000 description 1
- 229910052763 palladium Inorganic materials 0.000 description 1
- 125000001147 pentyl group Chemical group C(CCCC)* 0.000 description 1
- 125000001997 phenyl group Chemical group [H]C1=C([H])C([H])=C(*)C([H])=C1[H] 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- 229920001748 polybutylene Polymers 0.000 description 1
- 229920000570 polyether Polymers 0.000 description 1
- 229920001451 polypropylene glycol Polymers 0.000 description 1
- 239000010970 precious metal Substances 0.000 description 1
- 125000002924 primary amino group Chemical group [H]N([H])* 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000011946 reduction process Methods 0.000 description 1
- 229910052703 rhodium Inorganic materials 0.000 description 1
- 239000010948 rhodium Substances 0.000 description 1
- MHOVAHRLVXNVSD-UHFFFAOYSA-N rhodium atom Chemical compound [Rh] MHOVAHRLVXNVSD-UHFFFAOYSA-N 0.000 description 1
- 229910052701 rubidium Inorganic materials 0.000 description 1
- IGLNJRXAVVLDKE-UHFFFAOYSA-N rubidium atom Chemical compound [Rb] IGLNJRXAVVLDKE-UHFFFAOYSA-N 0.000 description 1
- 229910052707 ruthenium Inorganic materials 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 238000004626 scanning electron microscopy Methods 0.000 description 1
- 229910052711 selenium Inorganic materials 0.000 description 1
- 239000011669 selenium Substances 0.000 description 1
- 150000003378 silver Chemical class 0.000 description 1
- HKZLPVFGJNLROG-UHFFFAOYSA-M silver monochloride Chemical compound [Cl-].[Ag+] HKZLPVFGJNLROG-UHFFFAOYSA-M 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
- 239000010937 tungsten Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B3/00—Extraction of metal compounds from ores or concentrates by wet processes
- C22B3/04—Extraction of metal compounds from ores or concentrates by wet processes by leaching
- C22B3/16—Extraction of metal compounds from ores or concentrates by wet processes by leaching in organic solutions
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
Definitions
- This invention relates to the recovery of metals from waste or scrap meterials and in particular to a process in which free metals are obtained by reduction of chemically combined forms of the metals under mild, readily controlled conditions .
- the reducing capability of the alkali metals is well known.
- the oxidation potentials of these metals range from +2.71 volts for sodium to +3.05 volts for lithium, the oxidation potential being a measure of the reducing strength of the metal.
- the present invention provides a process for recovering metals that are lower than the alkali metals in the electromotive force series from metal-containing materials in which the metal is present in chemically combined form.
- metal in chemically combined formed or “chemically combined form of a metal” are intended to signify that the metal is associated with other chemical substances in a stable aggregate, such as a chemical compound held together by covalent, ionic, or hydrogen bonds, a complex formed from a central metal atom and a number of bound groups, or ligands, or any other stable arrangement that a metal may assume.
- the process involves the use of a reagent produced by the reaction between an alkali metal or hydroxide thereof, a polyglycol or derivative thereof, and oxygen. By contacting the metal containing material with this reagent, the metal is readily recoverable in elemental form from the metal- containing material.
- the reagent employed in the practice of this invention has excellent reducing properties, and its preparation and use may be carried out under moderate operating conditions with the simplest of equipment. Description of the Invention
- the alkali metals normally employed to produce the aforesaid reagent include lithium, sodium and potassium and amalgams of these metals, with sodium and potassium being preferred. Any of the alkali metal hydroxides may be used in practicing the method of the present invention.
- the hydroxides of lithium, sodium and potassium, or mixtures thereof, are preferred because of their ready availability and relatively low cost. Of these, sodium hydroxide is particularly preferred.
- Solid alkali metal hydroxide or an aqueous solution thereof may be used to produce the reagent.
- R2 wherein R is hydrogen or lower-alky1, R j _ and R2 are the same or different and are selected from the group consisting of hydrogen, unsubstituted or substituted lower alkyl, unsubstituted or substituted cycloalkyl having from 5 to 8 carbon atoms, and unsubstituted or substituted aryl, "n” has a value from about 2 to about 400, and "x” has a value of at least 2, which includes polyglycols and polyglycol monalkyl ethers.
- the lower alkyl radical in the foregoing formula may be methyl, ethyl, propyl, butyl, isobutyl, pentyl or hexyl, i.e., the term lower alkyl embraces radicals having up to six carbon atoms.
- the cycloalkyl radical may be cyclopentyl, cyclohexyl, cycloheptyl and cyclooctyl.
- the aryl radical may be phenyl, benzyl, biphenyl, naphthyl, etc.
- the substitutents on the R-j and R2 radicals include, but are not limited to lower-alkyl, e.g.
- Suitable liquid reactants falling within the above formula include diethylene glycol, diethylene glycol monomethyl ether, polyether glycols, such as polyethylene glycols, polypropylene glycols, and polybutylene glycols and related long chain glycol monoalkyl ethers.
- the preferred liquid reactants are those of the above general formula wherein R ⁇ and R2 are hydrogen and x is 2. Particularly preferred are polyethylene glycols, i.e., polymers of the formula H ⁇ £CH 2 -CH2 ⁇ n H, having an average molecular weight range from about 100 to about 20,000.
- the above-described reactants may be either liquids or solids. Those which are solids should be melted before the reaction is begun. Neither low volatility, non-polar liquids, nor glycolic liquids in which both terminal hydroxyl groups are alkylated has been found to produce the desired reactivity.
- polyglycols as used herein, is intended to signify polymers of dihydric alchols .
- Oxygen is a necessary third reactant in the formation of the above-described reagent.
- the alkali metal and the compound of the above general formula react vigorously with the evolution of hydrogen gas.
- the reaction mixture takes on a deep amber color. This color change is distinct and readily observable and signals the formation of the reagent.
- the reactions involving alkali metal hydroxides proceed in generally the same way, except that no hydrogen gas is evolved. Attempts to carry out the reaction of sodium or sodium hydroxide with polyethylene glycol in an oxygen-free atmosphere have produced a relatively clear solution which was ineffective for carrying out the method of this invention.
- the decomposition reagent will be formed, as indicated by the aforementioned color change.
- the required reactants may be reacted simultaneously, or according to the two-step procedure just described.
- the reaction for producing the reagent proceeds spontaneously at room temperature simply by mixing the reactants in an open reaction vessel, preferably with stirring. It is unnecessary to bubble oxygen into the reaction mixture, for atmospheric oxygen satisfies the requirements of the reaction.
- the reaction mixture may be heated to accelerate the rate of reaction.
- the reaction mixture may be heated to a temperature in the range of 30 ⁇ C to about 200°C and proceeds very satisfactorily at a temperature between about 50°C and about 100 ⁇ C.
- the reaction may be conveniently carried out at atmospheric pressure with excellent results; superatmospheric pressure may be employed, if desired.
- the stoichiometry of the reaction requires one mole of alkali metal or alkali metal hydroxide per mole of compound of the above general formula.
- sodium metal and polyethylene glycol avg. M.W.
- reaction mixture for example, heating of the reaction mixture to between about 50°C and about 80°C gives a reasonable rate of reaction.
- the reaction becomes exothermic and the temperature of the reaction mixture rises to near or above the melting point of the sodium, which is 97.6 ⁇ C. With the rise in temperature, the sodium becomes molten and reaction with the liquid ensues .
- This reaction is considerably more exothermic than the reaction in which alkali metal hydroxides are employed as a starting material.
- the reagent may be used immediately, or it may be stored for later use.
- the reagent may be used immediately, or it may be stored for later use.
- ' reagent may be stored for at least six months without appreciably diminishing its reactivity.
- the recovery of a particular metal is accomplished simply by contacting the metal- containing material with the above-described decomposition reagent.
- the metal containing material may be ground up, comminuted or otherwise reduced to a relatively small particle size.
- the preferred temperature range for carrying out the recovery method is from about room temperature to about 250 ⁇ C.
- the reduced metal can be isolated or collected by any of the methods well known in the art, such as gravity settling or centrifugation.
- the viscosity of the reagent may be reduced by diluting it with a solvent.
- solvents are suitable for this purpose, including alcohols, ketones, and aliphatic and aromatic hydrocarbons. These are conveniently added to the reagent with stirring.
- metals can be recovered by the method of this invention which is generally applicable to the recovery of any metal that is lower in the electromotive force series than the particular alkali metal used in forming the reagent.
- the present method may be employed in the recovery of the metals of Group lb of the Periodic Table of the Elements, viz.
- This method may also be used to advantage in recovering the Group 8 metals, iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium and platinum.
- Other metals such as tin, cadmium, lead, molybdenum, beryllium, selenium and tungsten may also be recovered by the method of this invention.
- Example I Preparation of Decomposition Reagent and Recovery of Metallic Silver
- NaPEG sodium polyethylene glycol reagent
- PEG 400 polyethylene glycol having an average molecular weight of 400
- PEG 400 polyethylene glycol having an average molecular weight of 400
- the temperature of the mixture rose to about 120°C and was maintained as close as possible to that temperature until all of the sodium, which melted and formed a shiny layer of metallic globules on top of the solvent, had reacted. Reaction is indicated by the change in color of the PEG 400 to a dark amber and the disappearance of the metallic globules. If all of the sodium does not react, small additions of PEG 400 may be used to effect complete reaction. Alternatively, the NaPEG mixture may be placed in a separatory funnel and the lower NaPEG layer drawn off. The
- f OMPI unreacted sodium metal will rise to the top and may be removed by reaction with an alcohol, such as methanol.
- a decomposition reagent was prepared as described in Example I. To the reagent, there was added pulverized non-magnetic cobalt oxide. Again, almost immediately, there was deposited on the bottom of the vessel reflective metallic particles. These particles were ferromagnetic as indicated by their attraction to a magnetic stirring bar. The particles were determined to be pure cobalt metal by scanning electron microscopy.
Abstract
Valuable metals are recovered from metal-containing materials, such as scrap or waste materials, in which the metal is present in chemically combined form, by a process which comprises contacting the metal-containing material with a reagent comprising the product of the reaction of an alkali metal or alkali metal hydroxide with a polyglycol or a polyglycol monoalkyl ether and oxygen.
Description
METHOD OF RECOVERING METALS FROM METAL CONTAINING MATERIALS
Background of the Invention
This invention relates to the recovery of metals from waste or scrap meterials and in particular to a process in which free metals are obtained by reduction of chemically combined forms of the metals under mild, readily controlled conditions .
The reducing capability of the alkali metals, lithium, sodium, potassium, rubidium and cesium, is well known. The oxidation potentials of these metals range from +2.71 volts for sodium to +3.05 volts for lithium, the oxidation potential being a measure of the reducing strength of the metal. These high values place the alkali metal at the top of the electromotive force series, indicating that, in theory, they will reduce virtually any oxidizing agent no matter how weak.
As a practical matter the full reducing capability of the alkali metals has remained largely unrealized. For example, sodium has been used extensively in the form of its solution in liquid ammonia for the production of metals from their salts, however, its reducing properties are appreciably diminished in this form, in comparison with the pure metal. Reduction processes which have been developed heretofore employing pure alkali metals have proven to be generally unsatisfactory in that they are operable on a relatively small scale, require specialized equipment, and often involve rather extreme operating conditions, such as complete exclusion of air and
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water.
Presently, considerable amounts of precious and other useful metals are disposed of each year because of the difficulty of recovering the metal economically by currently available technology. For example, exposed photographic film containing silver salts, and mine tailings containing appreciable quantities of metal ores are simply discarded because recovery by presently available methods is generally unprofitable.
The desirability of a commercially practicable method employing alkali metals for the recovery of a wide variety of less reactive metals by chemical reduction has led to the development of the present invention.
Summary of the Invention
The present invention provides a process for recovering metals that are lower than the alkali metals in the electromotive force series from metal-containing materials in which the metal is present in chemically combined form. As used herein, the expressions "metal in chemically combined formed" or "chemically combined form of a metal" are intended to signify that the metal is associated with other chemical substances in a stable aggregate, such as a chemical compound held together by covalent, ionic, or hydrogen bonds, a complex formed from a central metal atom and a number of bound groups, or ligands, or any other stable arrangement that a metal may assume. The process involves the use of a reagent produced by the reaction between an alkali metal or hydroxide thereof, a polyglycol or derivative thereof, and oxygen. By contacting the metal
containing material with this reagent, the metal is readily recoverable in elemental form from the metal- containing material.
The reagent employed in the practice of this invention has excellent reducing properties, and its preparation and use may be carried out under moderate operating conditions with the simplest of equipment. Description of the Invention
The alkali metals normally employed to produce the aforesaid reagent include lithium, sodium and potassium and amalgams of these metals, with sodium and potassium being preferred. Any of the alkali metal hydroxides may be used in practicing the method of the present invention. The hydroxides of lithium, sodium and potassium, or mixtures thereof, are preferred because of their ready availability and relatively low cost. Of these, sodium hydroxide is particularly preferred.
Solid alkali metal hydroxide or an aqueous solution thereof may be used to produce the reagent.
However, to the extent that the hydroxide and/or water may interfere with the recovery of the free metal, as, for example, by the formation of insoluble metal hydroxides, the presence of these substances in the reagent should be avoided.
The alkali metal or hydroxide is reacted with a compound of the general formula:
Rl HO - C(C)χ -0]n- R,
R2 wherein R is hydrogen or lower-alky1, Rj_ and R2 are the same or different and are selected from the group consisting of hydrogen, unsubstituted or
substituted lower alkyl, unsubstituted or substituted cycloalkyl having from 5 to 8 carbon atoms, and unsubstituted or substituted aryl, "n" has a value from about 2 to about 400, and "x" has a value of at least 2, which includes polyglycols and polyglycol monalkyl ethers. The lower alkyl radical in the foregoing formula may be methyl, ethyl, propyl, butyl, isobutyl, pentyl or hexyl, i.e., the term lower alkyl embraces radicals having up to six carbon atoms. The cycloalkyl radical may be cyclopentyl, cyclohexyl, cycloheptyl and cyclooctyl. The aryl radical may be phenyl, benzyl, biphenyl, naphthyl, etc. The substitutents on the R-j and R2 radicals include, but are not limited to lower-alkyl, e.g. methyl, ethyl, propyl, butyl, isobutyl, etc,; halo, e.g. chloro, bromo; nitro7 sulfato; carboxyl; amino; mono-and di-lower-alkylamino, e.g. methylethylamino; amido; hydroxy; lower alkoxy, e.g. methoxy, ethoxy, etc. Suitable liquid reactants falling within the above formula include diethylene glycol, diethylene glycol monomethyl ether, polyether glycols, such as polyethylene glycols, polypropylene glycols, and polybutylene glycols and related long chain glycol monoalkyl ethers. The preferred liquid reactants are those of the above general formula wherein R^ and R2 are hydrogen and x is 2. Particularly preferred are polyethylene glycols, i.e., polymers of the formula Hθ£CH2-CH2θ nH, having an average molecular weight range from about 100 to about 20,000. The above-described reactants may be either liquids or solids. Those which are solids should be melted before the reaction is begun. Neither low volatility,
non-polar liquids, nor glycolic liquids in which both terminal hydroxyl groups are alkylated has been found to produce the desired reactivity.
The term "polyglycols", as used herein, is intended to signify polymers of dihydric alchols .
Oxygen is a necessary third reactant in the formation of the above-described reagent. When the formation of the reagent is carried out in the presence of air, for example, the alkali metal and the compound of the above general formula react vigorously with the evolution of hydrogen gas. When reaction occurs, the reaction mixture takes on a deep amber color. This color change is distinct and readily observable and signals the formation of the reagent. The reactions involving alkali metal hydroxides proceed in generally the same way, except that no hydrogen gas is evolved. Attempts to carry out the reaction of sodium or sodium hydroxide with polyethylene glycol in an oxygen-free atmosphere have produced a relatively clear solution which was ineffective for carrying out the method of this invention. However, it has been found that when sodium or sodium hydroxide and polyethylene glycol are reacted in an atmosphere consisting essentially of nitrogen, and oxygen is thereafter introduced into the resultant solution, the decomposition reagent will be formed, as indicated by the aforementioned color change. Thus, the required reactants may be reacted simultaneously, or according to the two-step procedure just described. When using an alkali metal, the two-step procedure is advantageous in that it avoids having a potentially explosive mixture of hydrogen and oxygen present in the reaction system.
Generally, the reaction for producing the reagent proceeds spontaneously at room temperature simply by mixing the reactants in an open reaction vessel, preferably with stirring. It is unnecessary to bubble oxygen into the reaction mixture, for atmospheric oxygen satisfies the requirements of the reaction. Thus, no temperature control or specialized equipment is required for carrying out the reaction. If desired, the reaction mixture may be heated to accelerate the rate of reaction. The reaction mixture may be heated to a temperature in the range of 30βC to about 200°C and proceeds very satisfactorily at a temperature between about 50°C and about 100βC. The reaction may be conveniently carried out at atmospheric pressure with excellent results; superatmospheric pressure may be employed, if desired. The stoichiometry of the reaction requires one mole of alkali metal or alkali metal hydroxide per mole of compound of the above general formula. In the reaction between sodium metal and polyethylene glycol (avg. M.W. 400), for example, heating of the reaction mixture to between about 50°C and about 80°C gives a reasonable rate of reaction. Upon heating, the reaction becomes exothermic and the temperature of the reaction mixture rises to near or above the melting point of the sodium, which is 97.6βC. With the rise in temperature, the sodium becomes molten and reaction with the liquid ensues . This reaction is considerably more exothermic than the reaction in which alkali metal hydroxides are employed as a starting material.
Once formed, the reagent may be used immediately, or it may be stored for later use. In general, the
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reagent may be stored for at least six months without appreciably diminishing its reactivity.
As indicated above, the recovery of a particular metal is accomplished simply by contacting the metal- containing material with the above-described decomposition reagent. In order to bring about effective contact between the metal in its combined form and the decomposition reagent, the metal containing material may be ground up, comminuted or otherwise reduced to a relatively small particle size. The preferred temperature range for carrying out the recovery method is from about room temperature to about 250βC. The reduced metal can be isolated or collected by any of the methods well known in the art, such as gravity settling or centrifugation.
Ordinarily, heating of the reaction mixture to a temperature as high as 250°C will be required only when the reagent is relatively viscous. In such cases, the viscosity of the reagent may be reduced by diluting it with a solvent. A wide variety of solvents are suitable for this purpose, including alcohols, ketones, and aliphatic and aromatic hydrocarbons. These are conveniently added to the reagent with stirring. A wide variety of metals can be recovered by the method of this invention which is generally applicable to the recovery of any metal that is lower in the electromotive force series than the particular alkali metal used in forming the reagent. Thus, the present method may be employed in the recovery of the metals of Group lb of the Periodic Table of the Elements, viz. copper, silver and gold. This method may also be used to advantage in recovering the Group 8 metals,
iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium and platinum. Other metals, such as tin, cadmium, lead, molybdenum, beryllium, selenium and tungsten may also be recovered by the method of this invention.
The invention is more fully illustrated in the following examples.
Example I - Preparation of Decomposition Reagent and Recovery of Metallic Silver A sodium polyethylene glycol reagent (referred to in these examples as NaPEG) was prepared by placing 900 ml of polyethylene glycol having an average molecular weight of 400 (referred to in these examples as PEG 400) in a 3000 ml beaker and heating until the temperature approached 80°C. Stirring was accomplished by using an efficient overhead mechanical stirrer. A magnetic stirring assembly may also be used. Thereafter, approximately 55 grams of freshly cut sodium metal was added, all within a two minute period. The normal precautions for the handling of metallic sodium should be taken in carrying out the reaction. Within ten minutes the temperature of the mixture rose to about 120°C and was maintained as close as possible to that temperature until all of the sodium, which melted and formed a shiny layer of metallic globules on top of the solvent, had reacted. Reaction is indicated by the change in color of the PEG 400 to a dark amber and the disappearance of the metallic globules. If all of the sodium does not react, small additions of PEG 400 may be used to effect complete reaction. Alternatively, the NaPEG mixture may be placed in a separatory funnel and the lower NaPEG layer drawn off. The
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unreacted sodium metal will rise to the top and may be removed by reaction with an alcohol, such as methanol.
To the decomposition agent, maintained in the beaker at about 100βC, there was added with stirring a quantity of ground up waste material containing Ag2Sθ4« Almost immediately, finely divided silver metal was deposited on the bottom of the beaker.
Similar results may be obtained with pulverized waste material containing other precious metal compounds, such as AgOOCCH3, Ag2θ, and AgCl, or complexes, such as Au(C )4 .
Example II - Recovery of Cobalt
A decomposition reagent was prepared as described in Example I. To the reagent, there was added pulverized non-magnetic cobalt oxide. Again, almost immediately, there was deposited on the bottom of the vessel reflective metallic particles. These particles were ferromagnetic as indicated by their attraction to a magnetic stirring bar. The particles were determined to be pure cobalt metal by scanning electron microscopy.
Those skilled in the art will appreciate that the description of this invention set forth in the foregoing specification and examples is intended merely to illustrate and not to limit the invention. It will also be appreciated that the implementation of the above-described process is capable of wide variation and modification without departing from the spirit and scope of the invention as set forth in the appended claims .
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Claims
1. A method for recovering a metal that is lower than the alkali metals in the electromotive force series from a material containing said metal in chemically combined form, said method comprising: a. providing a reagent comprising the product of the reaction of an alkali metal or alkali metal hydroxide, a reactant having the general formula
HO £(C)x-03n R,
R2 wherein R is hydrogen or lower alkyl, R-ι_ and R2 are the same or different and are selected from the group consisting of hydrogen, unsubstituted or substituted lower alkyl, unsubstituted or substituted cycloalkyl having from 5 to 8 carbon atoms, and unsubstituted or substituted aryl, n has a value from about 2 to about 400 and x has a value of at least 2, and oxygen; b. contacting said decomposition reagent with said metal-containing material; and c. recovering the free metal.
2. The method claimed in claim 1 wherein said decomposition reagent is produced from an alkali metal selected from the group consisting of sodium, lithium, potassium and amalgams thereof and a reactant of the above general formula wherein Rj_ and R2 are hydrogen and x is 2.
3. The method claimed in claim 1 wherein the decomposition reagent is produced from sodium and polyethylene glycol.
4. The method of claim 1 wherein the contacting step is carried out at a temperature between about room temperature and about 250°C.
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5. The method of claim 1 wherein the reagent is diluted with a solvent selected from the group consisting of alcohols, ketones, and aliphatic and aromatic hydrocarbons.
6. The method of claim 1 wherein the metal recovered is from Group lb of the Periodic Table of the Elements.
7. The method of claim 1 wherein the metal recovered is from Group 8 of the Periodic Table of the Elements.
"fc
OMPI WIPO
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP57502759A JPS59501369A (en) | 1982-08-04 | 1982-08-04 | How to recover metals from metal-containing materials |
PCT/US1982/001059 WO1984000562A1 (en) | 1982-08-04 | 1982-08-04 | Method of recovering metals from metal containing materials |
DK1663/84A DK166384D0 (en) | 1982-08-04 | 1984-03-23 | METHOD OF RECOVERING METALS FROM METAL CONTAINING MATERIALS |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/US1982/001059 WO1984000562A1 (en) | 1982-08-04 | 1982-08-04 | Method of recovering metals from metal containing materials |
Publications (1)
Publication Number | Publication Date |
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WO1984000562A1 true WO1984000562A1 (en) | 1984-02-16 |
Family
ID=22168126
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US1982/001059 WO1984000562A1 (en) | 1982-08-04 | 1982-08-04 | Method of recovering metals from metal containing materials |
Country Status (3)
Country | Link |
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JP (1) | JPS59501369A (en) |
DK (1) | DK166384D0 (en) |
WO (1) | WO1984000562A1 (en) |
Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US553115A (en) * | 1896-01-14 | Reff galbraith | ||
US1350157A (en) * | 1920-01-13 | 1920-08-17 | Frederick W Horton | Process for treating celluloid products |
US3826755A (en) * | 1970-08-26 | 1974-07-30 | Atomic Energy Authority Uk | Process for precipitating metal-containing compounds as gel-particles dispersed in aqueous phase |
US3833353A (en) * | 1972-07-19 | 1974-09-03 | P Taylor | Process for class viiib metals ore reduction |
US3833351A (en) * | 1973-02-15 | 1974-09-03 | Univ Eng Inc | Continuous preparation of pure metals by hydrogen reduction |
US3885955A (en) * | 1973-06-08 | 1975-05-27 | Demetron | Process for the production of gold powder |
US3892557A (en) * | 1973-06-15 | 1975-07-01 | Demetron Ges Fur Elecktronik W | Process for the production of gold powder in platelet form |
US3899322A (en) * | 1972-06-20 | 1975-08-12 | Rockwell International Corp | Noble-type metal recovery process by use of molten salt bath |
-
1982
- 1982-08-04 WO PCT/US1982/001059 patent/WO1984000562A1/en unknown
- 1982-08-04 JP JP57502759A patent/JPS59501369A/en active Pending
-
1984
- 1984-03-23 DK DK1663/84A patent/DK166384D0/en not_active IP Right Cessation
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US553115A (en) * | 1896-01-14 | Reff galbraith | ||
US1350157A (en) * | 1920-01-13 | 1920-08-17 | Frederick W Horton | Process for treating celluloid products |
US3826755A (en) * | 1970-08-26 | 1974-07-30 | Atomic Energy Authority Uk | Process for precipitating metal-containing compounds as gel-particles dispersed in aqueous phase |
US3899322A (en) * | 1972-06-20 | 1975-08-12 | Rockwell International Corp | Noble-type metal recovery process by use of molten salt bath |
US3833353A (en) * | 1972-07-19 | 1974-09-03 | P Taylor | Process for class viiib metals ore reduction |
US3833351A (en) * | 1973-02-15 | 1974-09-03 | Univ Eng Inc | Continuous preparation of pure metals by hydrogen reduction |
US3885955A (en) * | 1973-06-08 | 1975-05-27 | Demetron | Process for the production of gold powder |
US3892557A (en) * | 1973-06-15 | 1975-07-01 | Demetron Ges Fur Elecktronik W | Process for the production of gold powder in platelet form |
Non-Patent Citations (2)
Title |
---|
Glycols, issued 1952, (George Curme, Editor) Reinhold Publishing Corporation, N.Y., Page 114 * |
The Systematic Identification of Organic Compounds, issued May 1962, Fourth Edition, Ralph Shrines et al:, John Wiley and Sons, N.Y., Pages 147-149 * |
Also Published As
Publication number | Publication date |
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DK166384A (en) | 1984-03-23 |
DK166384D0 (en) | 1984-03-23 |
JPS59501369A (en) | 1984-08-02 |
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