CN114712893A - Method for recovering gold in thiosulfate solution - Google Patents
Method for recovering gold in thiosulfate solution Download PDFInfo
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- CN114712893A CN114712893A CN202210304653.3A CN202210304653A CN114712893A CN 114712893 A CN114712893 A CN 114712893A CN 202210304653 A CN202210304653 A CN 202210304653A CN 114712893 A CN114712893 A CN 114712893A
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- Prior art keywords
- gold
- polyacrylonitrile fiber
- thiosulfate
- thiosulfate solution
- functionalized
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- 239000010931 gold Substances 0.000 title claims abstract description 138
- 229910052737 gold Inorganic materials 0.000 title claims abstract description 99
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 title claims abstract description 92
- 238000000034 method Methods 0.000 title claims abstract description 51
- DHCDFWKWKRSZHF-UHFFFAOYSA-N sulfurothioic S-acid Chemical compound OS(O)(=O)=S DHCDFWKWKRSZHF-UHFFFAOYSA-N 0.000 title claims abstract 15
- 239000000835 fiber Substances 0.000 claims abstract description 94
- 229920002239 polyacrylonitrile Polymers 0.000 claims abstract description 85
- 238000002386 leaching Methods 0.000 claims abstract description 30
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 claims abstract description 26
- 238000010992 reflux Methods 0.000 claims abstract description 26
- 229910000147 aluminium phosphate Inorganic materials 0.000 claims abstract description 13
- 239000000126 substance Substances 0.000 claims abstract description 11
- 150000001412 amines Chemical class 0.000 claims abstract description 10
- 239000000203 mixture Substances 0.000 claims abstract description 10
- 238000011084 recovery Methods 0.000 claims abstract description 8
- 238000005406 washing Methods 0.000 claims abstract description 7
- 230000007935 neutral effect Effects 0.000 claims abstract description 6
- 125000001841 imino group Chemical group [H]N=* 0.000 claims abstract description 3
- 125000002924 primary amino group Chemical group [H]N([H])* 0.000 claims abstract description 3
- 238000001179 sorption measurement Methods 0.000 claims description 26
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 15
- 239000003153 chemical reaction reagent Substances 0.000 claims description 13
- 239000008367 deionised water Substances 0.000 claims description 13
- 229910021641 deionized water Inorganic materials 0.000 claims description 13
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 11
- VILCJCGEZXAXTO-UHFFFAOYSA-N 2,2,2-tetramine Chemical compound NCCNCCNCCN VILCJCGEZXAXTO-UHFFFAOYSA-N 0.000 claims description 10
- 238000006243 chemical reaction Methods 0.000 claims description 10
- ISIJQEHRDSCQIU-UHFFFAOYSA-N tert-butyl 2,7-diazaspiro[4.5]decane-7-carboxylate Chemical compound C1N(C(=O)OC(C)(C)C)CCCC11CNCC1 ISIJQEHRDSCQIU-UHFFFAOYSA-N 0.000 claims description 10
- 229960001124 trientine Drugs 0.000 claims description 10
- FAGUFWYHJQFNRV-UHFFFAOYSA-N tetraethylenepentamine Chemical compound NCCNCCNCCNCCN FAGUFWYHJQFNRV-UHFFFAOYSA-N 0.000 claims description 8
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 claims description 6
- 238000001035 drying Methods 0.000 claims description 6
- ACVYVLVWPXVTIT-UHFFFAOYSA-N phosphinic acid Chemical compound O[PH2]=O ACVYVLVWPXVTIT-UHFFFAOYSA-N 0.000 claims description 6
- 238000002156 mixing Methods 0.000 claims description 5
- IKHGUXGNUITLKF-UHFFFAOYSA-N Acetaldehyde Chemical compound CC=O IKHGUXGNUITLKF-UHFFFAOYSA-N 0.000 claims description 4
- RPNUMPOLZDHAAY-UHFFFAOYSA-N Diethylenetriamine Chemical compound NCCNCCN RPNUMPOLZDHAAY-UHFFFAOYSA-N 0.000 claims description 4
- 239000003463 adsorbent Substances 0.000 claims description 4
- PTMHPRAIXMAOOB-UHFFFAOYSA-N phosphoramidic acid Chemical compound NP(O)(O)=O PTMHPRAIXMAOOB-UHFFFAOYSA-N 0.000 claims description 4
- 239000004698 Polyethylene Substances 0.000 claims description 2
- 239000012535 impurity Substances 0.000 claims description 2
- 229920000768 polyamine Polymers 0.000 claims description 2
- -1 polyethylene Polymers 0.000 claims description 2
- 229920000573 polyethylene Polymers 0.000 claims description 2
- 238000002360 preparation method Methods 0.000 claims description 2
- 125000002485 formyl group Chemical class [H]C(*)=O 0.000 claims 3
- 239000000463 material Substances 0.000 abstract description 9
- 150000001299 aldehydes Chemical class 0.000 abstract description 4
- 229910052799 carbon Inorganic materials 0.000 abstract description 4
- 238000000605 extraction Methods 0.000 abstract description 4
- 238000009854 hydrometallurgy Methods 0.000 abstract description 3
- 238000004519 manufacturing process Methods 0.000 abstract description 3
- 230000007613 environmental effect Effects 0.000 abstract description 2
- 239000002440 industrial waste Substances 0.000 abstract description 2
- 230000004048 modification Effects 0.000 abstract description 2
- 238000012986 modification Methods 0.000 abstract description 2
- 239000010970 precious metal Substances 0.000 abstract description 2
- DHCDFWKWKRSZHF-UHFFFAOYSA-L thiosulfate(2-) Chemical compound [O-]S([S-])(=O)=O DHCDFWKWKRSZHF-UHFFFAOYSA-L 0.000 description 37
- 239000007788 liquid Substances 0.000 description 11
- 238000003756 stirring Methods 0.000 description 10
- 238000011068 loading method Methods 0.000 description 9
- 238000004364 calculation method Methods 0.000 description 8
- 239000003607 modifier Substances 0.000 description 8
- 239000007787 solid Substances 0.000 description 7
- WSFSSNUMVMOOMR-NJFSPNSNSA-N methanone Chemical compound O=[14CH2] WSFSSNUMVMOOMR-NJFSPNSNSA-N 0.000 description 5
- 230000000694 effects Effects 0.000 description 4
- IKHGUXGNUITLKF-XPULMUKRSA-N acetaldehyde Chemical compound [14CH]([14CH3])=O IKHGUXGNUITLKF-XPULMUKRSA-N 0.000 description 3
- 238000004070 electrodeposition Methods 0.000 description 3
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- XFXPMWWXUTWYJX-UHFFFAOYSA-N Cyanide Chemical compound N#[C-] XFXPMWWXUTWYJX-UHFFFAOYSA-N 0.000 description 2
- 230000018109 developmental process Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 229910052698 phosphorus Inorganic materials 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- 238000000638 solvent extraction Methods 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- 238000005349 anion exchange Methods 0.000 description 1
- 229910052785 arsenic Inorganic materials 0.000 description 1
- RQNWIZPPADIBDY-UHFFFAOYSA-N arsenic atom Chemical compound [As] RQNWIZPPADIBDY-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000009920 chelation Effects 0.000 description 1
- ZPUCINDJVBIVPJ-LJISPDSOSA-N cocaine Chemical compound O([C@H]1C[C@@H]2CC[C@@H](N2C)[C@H]1C(=O)OC)C(=O)C1=CC=CC=C1 ZPUCINDJVBIVPJ-LJISPDSOSA-N 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- QKSIFUGZHOUETI-UHFFFAOYSA-N copper;azane Chemical compound N.N.N.N.[Cu+2] QKSIFUGZHOUETI-UHFFFAOYSA-N 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000011549 displacement method Methods 0.000 description 1
- 229910001254 electrum Inorganic materials 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 125000004185 ester group Chemical group 0.000 description 1
- ZBKIUFWVEIBQRT-UHFFFAOYSA-N gold(1+) Chemical compound [Au+] ZBKIUFWVEIBQRT-UHFFFAOYSA-N 0.000 description 1
- MXZVHYUSLJAVOE-UHFFFAOYSA-N gold(3+);tricyanide Chemical compound [Au+3].N#[C-].N#[C-].N#[C-] MXZVHYUSLJAVOE-UHFFFAOYSA-N 0.000 description 1
- 239000010940 green gold Substances 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 1
- 229910052753 mercury Inorganic materials 0.000 description 1
- 125000002560 nitrile group Chemical group 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 231100000252 nontoxic Toxicity 0.000 description 1
- 230000003000 nontoxic effect Effects 0.000 description 1
- 231100000956 nontoxicity Toxicity 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 230000005588 protonation Effects 0.000 description 1
- 230000008929 regeneration Effects 0.000 description 1
- 238000011069 regeneration method Methods 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D15/00—Separating processes involving the treatment of liquids with solid sorbents; Apparatus therefor
- B01D15/08—Selective adsorption, e.g. chromatography
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/22—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising organic material
- B01J20/26—Synthetic macromolecular compounds
- B01J20/265—Synthetic macromolecular compounds modified or post-treated polymers
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/28—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties
- B01J20/28014—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties characterised by their form
- B01J20/28023—Fibres or filaments
-
- 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
- C22B11/00—Obtaining noble metals
-
- 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
- C22B3/20—Treatment or purification of solutions, e.g. obtained by leaching
- C22B3/22—Treatment or purification of solutions, e.g. obtained by leaching by physical processes, e.g. by filtration, by magnetic means, or by thermal decomposition
- C22B3/24—Treatment or purification of solutions, e.g. obtained by leaching by physical processes, e.g. by filtration, by magnetic means, or by thermal decomposition by adsorption on solid substances, e.g. by extraction with solid resins
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- D—TEXTILES; PAPER
- D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
- D06M—TREATMENT, NOT PROVIDED FOR ELSEWHERE IN CLASS D06, OF FIBRES, THREADS, YARNS, FABRICS, FEATHERS OR FIBROUS GOODS MADE FROM SUCH MATERIALS
- D06M11/00—Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with inorganic substances or complexes thereof; Such treatment combined with mechanical treatment, e.g. mercerising
- D06M11/68—Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with inorganic substances or complexes thereof; Such treatment combined with mechanical treatment, e.g. mercerising with phosphorus or compounds thereof, e.g. with chlorophosphonic acid or salts thereof
- D06M11/70—Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with inorganic substances or complexes thereof; Such treatment combined with mechanical treatment, e.g. mercerising with phosphorus or compounds thereof, e.g. with chlorophosphonic acid or salts thereof with oxides of phosphorus; with hypophosphorous, phosphorous or phosphoric acids or their salts
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- D—TEXTILES; PAPER
- D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
- D06M—TREATMENT, NOT PROVIDED FOR ELSEWHERE IN CLASS D06, OF FIBRES, THREADS, YARNS, FABRICS, FEATHERS OR FIBROUS GOODS MADE FROM SUCH MATERIALS
- D06M13/00—Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with non-macromolecular organic compounds; Such treatment combined with mechanical treatment
- D06M13/322—Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with non-macromolecular organic compounds; Such treatment combined with mechanical treatment with compounds containing nitrogen
- D06M13/325—Amines
- D06M13/332—Di- or polyamines
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J2220/00—Aspects relating to sorbent materials
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- D06M2101/00—Chemical constitution of the fibres, threads, yarns, fabrics or fibrous goods made from such materials, to be treated
- D06M2101/16—Synthetic fibres, other than mineral fibres
- D06M2101/18—Synthetic fibres consisting of macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
- D06M2101/26—Polymers or copolymers of unsaturated carboxylic acids or derivatives thereof
- D06M2101/28—Acrylonitrile; Methacrylonitrile
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- 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
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Abstract
The invention discloses a method for recovering gold in thiosulfate solution, belonging to the technical field of hydrometallurgy and precious metal recovery. The invention isThe method comprises using a mixture containing amino (-NH) and imino (-NR)2) The organic amine substance modified polyacrylonitrile fiber is washed to be neutral and dried; and then carrying out two-step modification by using aminated polyacrylonitrile fiber, aldehydes and phosphoric acid substances under reflux at a fixed temperature, and washing to be neutral to obtain the modified material. The functionalized polyacrylonitrile fiber prepared by the method can effectively adsorb and recover gold (Au (S) in thiosulfate gold leaching solution2O3)2 3‑) (ii) a The used materials belong to the secondary utilization of industrial wastes, accord with the low-carbon environmental protection concept and have low cost. The material can efficiently recover gold (Au (S) in thiosulfate solution in short time2O3)2 3‑) The method is suitable for actual production and is not easy to pulverize, and has important significance for the industrial development of thiosulfate gold extraction technology.
Description
Technical Field
The invention relates to a method for recovering gold in thiosulfate solution, belonging to the technical field of hydrometallurgy and precious metal recovery.
Background
In the development of gold hydrometallurgy, the technology for extracting gold from ores is gradually developed from an initial mercury mixing method to a cyaniding method. To date, cyanidation is still the most prevalent method of gold extraction. However, the highly toxic cyanide in the method is easy to cause environmental pollution and ecological damage. Therefore, many non-cyanide gold extraction methods have been studied. The thiosulfate gold leaching method is considered to be a green gold leaching technology which is most likely to replace a cyanidation method due to the advantages of high gold leaching speed, no toxicity, low reagent cost, environmental friendliness, easiness in treatment of cyanide methods containing copper, arsenic and the like, difficulty in treatment of gold ores, no corrosion to equipment and the like. However, three main technical problems of (1) large consumption of thiosulfate, (2) high ammonia concentration required in the leaching process, (3) difficult gold recovery in the leaching solution and the like exist in a thiosulfate gold leaching system. The first two of these problems can be substantially solved by replacing them with copper-ammonia (amine) systems. Therefore, the effective recovery of gold in the immersion liquid becomes a core technical problem facing the realization of industrialization by a thiosulfate method.
To solve this problem more quickly, many methods have been studied to recover gold (Au (S) from thiosulfate gold baths2O3)2 3-). At present, four methods for recovering gold from thiosulfate gold leaching solution mainly comprise a displacement method, an adsorption method, a solvent extraction method and an electrodeposition method. The replacement method is difficult to be applied to actual production because the economic cost is too high when the replacement method is directly used for recovering gold in the thiosulfate gold leaching solution. Although the solvent extraction method has an advantage of high recovery rate, solid-liquid separation of the slurry is difficult and the consumption of the reagent is large. The electrodeposition method is suitable for gold separation at higher gold concentrations, but in practical thiosulfate bathsThe gold content is generally relatively low and is therefore not suitable for recovering gold from thiosulfate leach solutions and electrodeposition techniques for recovering gold from thiosulfate solutions are not yet mature. The adsorption method is favored by researchers due to the advantages of simple operation, low reagent cost and easy regeneration, but there are the problems that the resin is easy to be pulverized and is not suitable for the ore pulp environment and the active carbon can not be directly used for adsorbing and recovering gold (Au (S) in the thiosulfate gold leaching solution2O3)2 3-) (because the gold atom is far away from the surface of the carbon due to a coordinating group, a molecular structure space effect and the like). Therefore, an economical, efficient and rapid recovery of gold (Au (S) in thiosulfate leach solutions is sought2O3)2 3-) The method has important practical significance and certain necessity.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a method for recovering gold (Au (S) in thiosulfate solution2O3)2 3-) The method of (1), using certain functional atoms or groups contained in the functionalized polyacrylonitrile fiber and gold (Au (S) in a thiosulfate solution2O3)2 3-) Acts to achieve the adsorption effect.
In order to achieve the purpose, the invention adopts the following technical scheme: in the presence of (Au (S)2O3)2 3-) Adding amino phosphonic acid functionalized polyacrylonitrile fiber into the leachate to react with gold (Au (S) in the solution2O3)2 3-) Stirring and adsorbing;
the preparation method of the functionalized polyacrylonitrile fiber comprises the following steps:
(1) washing polyacrylonitrile fiber with deionized water to remove ash and impurities, and drying for later use.
(2) Mixing the polyacrylonitrile fiber in the step (1) with an organic amine reagent and deionized water, washing the mixture to be neutral by hot water after reflux reaction, and drying the mixture to obtain aminated polyacrylonitrile fiber for later use, wherein the mixing ratio of the polyacrylonitrile fiber to the organic amine reagent is 1g (20-100) ml, the deionized water is used as a solvent and does not participate in the reaction, and the amount is not limited.
(3) Carrying out reflux reaction on the aminated polyacrylonitrile fiber obtained in the step (2) and aldehydes, absolute ethyl alcohol and phosphoric acid substances, washing to be neutral to obtain aminophosphonic acid functionalized polyacrylonitrile fiber, and drying for later use; the proportion of the aminated polyacrylonitrile fiber, the aldehydes and the phosphoric acid substances is 1g, (10-30) ml, (3-8) g, the anhydrous ethanol is used as a solvent and does not participate in the reaction, and the amount is not limited.
Preferably, the polyacrylonitrile fiber in step (1) of the present invention is a polymer organic substance containing abundant nitrile group (-CN) and ester group (-COOR) groups.
Preferably, the organic amine reagent in step (2) of the present invention is a polyethylene polyamine containing amino and imino groups (-NH )2) And the concentration is more than 65%.
Further, the organic amine reagent in step (2) of the present invention is: one or a mixture of more of diethylenetriamine, triethylene tetramine and tetraethylenepentamine in any proportion.
Preferably, the amount of the aminophosphonic acid functionalized polyacrylonitrile fiber added to the thiosulfate gold leaching solution in the step (3) of the invention is 0.01-0.2 g/L; the gold content in the thiosulfate gold leaching solution is 2 kg/t-10 kg/t.
Preferably, the phosphoric acid substances in step (3) of the present invention are: one or more of hypophosphorous acid, phosphorous acid and phosphoric acid are mixed according to the proportion to obtain a mixture.
Preferably, the aldehydes in step (3) of the present invention are: one or two of formaldehyde and acetaldehyde are mixed according to any proportion.
Preferably, the temperature range of the reflux reaction in the step (2) of the invention is 100-140 ℃, and the time is 2-8 h; the temperature range of the reflux reaction in the step (3) is 50-90 ℃, and the time is 2-8 h.
The principle of the invention is as follows: from the above background, it is known that gold in a thiosulfate gold leaching solution is generally recovered by an adsorption method. Therefore, it is necessary to select materials which are low in cost and easy to modify. The method selects the polyacrylonitrile fiber which is rich in-CN and-COOR groups and easy to modify, adopts a chemical grafting modification means to respectively graft the groups containing N and P onto the surface of the polyacrylonitrile fiber by a two-step reflux method, and finally enables the gold in the thiosulfate gold-leaching solution to be effectively adsorbed by the functionalized polyacrylonitrile fiber.
The invention has the beneficial effects that:
(1) the method uses the industrial waste polyacrylonitrile fiber to adsorb gold in the thiosulfate solution, belongs to the secondary utilization of waste, is environment-friendly, accords with the low-carbon concept, and has the advantages of low reagent and adsorbent consumption and low reagent price; the material is easy to obtain, non-toxic and harmless, and has high adsorption capacity to gold.
(2) The material can efficiently recover gold (Au (S) in thiosulfate solution in short time2O3)2 3-) High efficiency recovery of (Au (S)2O3)2 3-) A method for gold (I) in solution; is suitable for actual production and has important significance for the industrial development of the thiosulfate gold extraction technology.
(3) The prepared functionalized polyacrylonitrile fiber can be used for treating gold (Au (S) in thiosulfate gold leaching solution2O3)2 3-) A good adsorption effect is achieved; the loading capacity of gold can reach 7 kg/t only by using 0.5g of adsorbing material, and the functionalized polyacrylonitrile fiber can be used for treating gold (Au (S) in thiosulfate gold leaching solution2O3)2 3-) The adsorption effect is generated because the grafted N performs protonation to form NRnH+OH-Form (1), OH after adsorption has taken place-And Au (S)2O3)2 3-With anion exchange and chelation between P and Au (i).
Detailed Description
The present invention will be further described with reference to the following detailed description, but the scope of the present invention is not limited to the description.
In the embodiment of the present invention, a self-prepared gold leaching solution is taken as an example, and gold in the gold leaching solution is gold (Au (S) in thiosulfate solution2O3)2 3-) The concentration of thiosulfate in the gold leaching solution is 0.01-0.4 mol/L, the concentration of gold is 5-65 mg/L, the stirring adsorption time is 0.05-24 h, the temperature is 25-65 ℃, and the solid-to-liquid ratio of the functionalized polyacrylonitrile fiber to the thiosulfate gold leaching solution is 1: 200-1: 50.
Example 1
In this example, diethylenetriamine and phosphorous acid are used as modifiers, and functionalized polyacrylonitrile fiber is used to recover gold Au (S) from thiosulfate solution2O3)2 3-The method comprises the following steps:
(1) and refluxing the cleaned polyacrylonitrile fiber, diethylenetriamine and deionized water at the ratio of 1g to 20ml to 10ml at 140 ℃ for 4 h to obtain the aminated polyacrylonitrile fiber.
(2) And (2) refluxing aminated polyacrylonitrile fiber, 40% formaldehyde, absolute ethyl alcohol and solid phosphorous acid at the temperature of 80 ℃ for 4 hours according to the proportion of 1g to 10ml to 25ml to 5g to obtain the functionalized polyacrylonitrile fiber.
(3) Taking 0.5g of the functional fiber adsorbent obtained in the step (2), adding the functional fiber adsorbent into a volume of 100 mL of Au (S)2O3)2 3-Para-gold Au (S) in gold leaching solution with concentration of 25mg/L2O3)2 3-Carrying out adsorption stirring, wherein the solid-liquid ratio is 1:200, the adsorption time is 24 h, and the initial pH is 9.0.
The loading of gold on the functionalized polyacrylonitrile fiber is 1.56 kg/t through calculation.
Example 2
In the embodiment, triethylene tetramine and phosphorous acid are used as modifiers, and functionalized polyacrylonitrile fiber is used for recovering gold Au (S) in thiosulfate solution2O3)2 3-The method comprises the following steps:
(1) and refluxing the cleaned polyacrylonitrile fiber, triethylene tetramine and deionized water at the ratio of 1g to 30 ml to 10ml at 140 ℃ for 4 hours to obtain the aminated polyacrylonitrile fiber.
(2) Taking aminated polyacrylonitrile fiber, and refluxing the aminated polyacrylonitrile fiber with 40% formaldehyde, absolute ethyl alcohol and solid phosphorous acid for 4 hours at 80 ℃ according to the proportion of 1g to 10ml to 25ml to 5g to obtain the functionalized polyacrylonitrile fiber.
(3) 0.5g of the functionalized fiber obtained in step (2) was added to a volume of 100 mL of Au (S)2O3)2 3-Para-gold Au (S) in gold leaching solution with concentration of 25mg/L2O3)2 3-Carrying out adsorption stirring, wherein the solid-liquid ratio is 1:200, the adsorption time is 24 h, and the initial pH is 9.0.
The loading capacity of gold on the functionalized polyacrylonitrile fiber is 7.00 kg/t through calculation.
Example 3
In the embodiment, tetraethylenepentamine and hypophosphorous acid are used as modifiers, and functionalized polyacrylonitrile fiber is used for recovering gold Au (S) in thiosulfate solution2O3)2 3-The method comprises the following steps:
(1) and refluxing the cleaned polyacrylonitrile fiber, tetraethylenepentamine and deionized water at the temperature of 140 ℃ for 4 hours according to the proportion of 1g to 40 ml to 10ml to obtain the aminated polyacrylonitrile fiber.
(2) Taking aminated polyacrylonitrile fiber, and refluxing the aminated polyacrylonitrile fiber with 40% acetaldehyde, anhydrous ethanol and solid hypophosphorous acid according to the proportion of 1g to 20ml to 25ml to 5g at 80 ℃ for 4 hours to obtain the functionalized polyacrylonitrile fiber.
(3) 0.5g of the functionalized fiber obtained in step (2) was added to a volume of 100 mL of Au (S)2O3)2 3-Para-gold Au (S) in gold leaching solution with concentration of 25mg/L2O3)2 3-And (3) performing adsorption stirring, wherein the solid-liquid ratio is 1:200, the adsorption time is 24 h, and the initial pH is 9.0.
The loading capacity of the gold on the functionalized polyacrylonitrile fiber is 2.54 kg/t through calculation.
Example 4
In the embodiment, triethylene tetramine and hypophosphorous acid are used as modifiers, and functionalized polyacrylonitrile fiber is used for recovering gold Au (S) in thiosulfate solution2O3)2 3-The method comprises the following steps:
(1) and refluxing the cleaned polyacrylonitrile fiber, triethylene tetramine and deionized water according to the proportion of 1g to 100 ml to 10ml at the temperature of 140 ℃ for 4 hours to obtain the aminated polyacrylonitrile fiber.
(2) Taking aminated polyacrylonitrile fiber, and refluxing the aminated polyacrylonitrile fiber with 40% of formaldehyde, anhydrous ethanol and hypophosphorous acid according to the proportion of 1g to 30 ml to 25ml to 3 g at the temperature of 80 ℃ for 4 hours to obtain the functionalized polyacrylonitrile fiber.
(3) 0.5g of the functionalized fiber obtained in step (2) was added to a volume of 100 mL of Au (S)2O3)2 3-gold-to-Au (S) in gold leaching solution with concentration of 25mg/L2O3)2 3-And (3) performing adsorption stirring, wherein the solid-liquid ratio is 1:200, the adsorption time is 24 h, and the initial pH is 9.0.
The loading of gold on the functionalized polyacrylonitrile fiber is 2.58 kg/t through calculation.
Example 5
In the embodiment, tetraethylenepentamine and phosphoric acid are used as modifiers, and functionalized polyacrylonitrile fiber is used for recovering gold Au (S) in thiosulfate solution2O3)2 3-The method comprises the following steps:
(1) and refluxing the cleaned polyacrylonitrile fiber, tetraethylenepentamine and deionized water at the temperature of 140 ℃ for 4 hours according to the proportion of 1g to 20ml to 10ml to obtain the aminated polyacrylonitrile fiber.
(2) Taking aminated polyacrylonitrile fiber, and refluxing the aminated polyacrylonitrile fiber with 40% acetaldehyde, anhydrous ethanol and solid phosphoric acid according to the proportion of 1g to 30 ml to 25ml to 5g at the temperature of 80 ℃ for 4 hours to obtain the functionalized polyacrylonitrile fiber.
(3) 0.5g of the functionalized fiber obtained in step (2) was added to a volume of 100 mL of Au (S)2O3)2 3-Para-gold Au (S) in gold leaching solution with concentration of 25mg/L2O3)2 3-Carrying out adsorption stirring, adjusting the initial pH to 6.0, the solid-liquid ratio to 1:200, and the adsorption time to 24 h.
The loading of gold on the functionalized polyacrylonitrile fiber was found to be 1.59 kg/t by calculation.
Example 6
In the embodiment, triethylene tetramine and phosphoric acid are used as modifiers, and functionalized polyacrylonitrile fiber is used for recovering gold Au (S) in thiosulfate solution2O3)2 3-The method comprises the following steps:
(1) and refluxing the cleaned polyacrylonitrile fiber, triethylene tetramine and deionized water at the ratio of 1g to 20ml to 10ml at 140 ℃ for 4 hours to obtain the aminated polyacrylonitrile fiber.
(2) And (2) taking the material obtained in the step (1), and refluxing the material, 40% of formaldehyde, anhydrous ethanol and solid phosphoric acid at the temperature of 80 ℃ for 4 hours according to the proportion of 1g to 10ml to 25ml to 8g to obtain the functionalized polyacrylonitrile fiber.
(3) 0.5g of the functionalized fiber obtained in step (2) was added to a volume of 100 mL of Au (S)2O3)2 3-Para-gold Au (S) in gold leaching solution with concentration of 25mg/L2O3)2 3-Carrying out adsorption stirring, adjusting the initial pH to 11.0, the solid-liquid ratio to 1:200, and the adsorption time to 24 h.
The loading capacity of the gold on the functionalized polyacrylonitrile fiber is 3.98 kg/t through calculation.
Example 7
In the embodiment, tetraethylenepentamine and phosphorous acid are used as modifiers, and functionalized polyacrylonitrile fiber is used for recovering gold Au (S) in thiosulfate solution2O3)2 3-The method comprises the following steps:
(1) and refluxing the cleaned polyacrylonitrile fiber, tetraethylenepentamine and deionized water at the temperature of 140 ℃ for 4 hours according to the proportion of 1g to 20ml to 10ml to obtain the aminated polyacrylonitrile fiber.
(2) Taking aminated polyacrylonitrile fiber, and refluxing the aminated polyacrylonitrile fiber with 40% acetaldehyde, absolute ethyl alcohol and solid phosphorous acid for 4 hours at 80 ℃ according to the proportion of 1g to 30 ml to 25ml to 8g to obtain the functionalized polyacrylonitrile fiber.
(3) 0.5g of the functionalized fiber obtained in step (2) was added to a volume of 100 mL of Au (S)2O3)2 3-gold-to-Au (S) in gold leaching solution with concentration of 25mg/L2O3)2 3-And (3) performing adsorption stirring, wherein the solid-liquid ratio is 1:200, the adsorption time is 24 h, and the initial pH is 9.0.
The loading capacity of the gold on the functionalized polyacrylonitrile fiber is 2.34 kg/t through calculation.
Example 8
In this example, triethylene tetramine and phosphorous acid modifier were used to recover gold Au (S) from thiosulfate solution using functionalized polyacrylonitrile fibers2O3)2 3-The method comprises the following steps:
(1) and refluxing the cleaned polyacrylonitrile fiber, triethylene tetramine and deionized water at the ratio of 1g to 20ml to 10ml at 140 ℃ for 4 hours to obtain the aminated polyacrylonitrile fiber.
(2) Taking aminated polyacrylonitrile fiber, and refluxing the aminated polyacrylonitrile fiber with 40% formaldehyde, absolute ethyl alcohol and solid phosphorous acid for 4 hours at 80 ℃ according to the proportion of 1g to 10ml to 25ml to 3 g to obtain the functionalized polyacrylonitrile fiber.
(3) 0.5g of the functionalized fiber obtained in step (2) was added to a volume of 100 mL of Au (S)2O3)2 3-Para-gold Au (S) in gold leaching solution with concentration of 25mg/L2O3)2 3-Carrying out adsorption stirring, wherein the solid-liquid ratio is 1:200, the adsorption time is 24 h, and the initial pH is 9.0.
The loading of gold on the functionalized polyacrylonitrile fiber was found to be 2.67 kg/t by calculation.
While the present invention has been described in detail with reference to the specific embodiments thereof, the present invention is not limited to the embodiments described above, and various changes can be made without departing from the spirit of the present invention within the knowledge of those skilled in the art.
Claims (8)
1. A method for recovering gold from a thiosulfate solution, characterized in that: putting the modified polyacrylonitrile fiber into thiosulfate gold leaching solution for adsorption and recovery (Au (S)2O3)2 3-)；
The preparation method of the functionalized polyacrylonitrile fiber comprises the following steps:
(1) washing polyacrylonitrile fibers with deionized water to remove ash and impurities, and drying for later use;
(2) mixing the polyacrylonitrile fiber in the step (1) with an organic amine reagent and deionized water, washing the mixture to be neutral by hot water after reflux reaction, and drying the mixture to obtain aminated polyacrylonitrile fiber for later use, wherein the mixing ratio of the polyacrylonitrile fiber to the organic amine reagent is 1g (20-100) ml;
(3) carrying out reflux reaction on the aminated polyacrylonitrile fiber obtained in the step (2) with aldehydes, absolute ethyl alcohol and phosphoric acid substances, washing to be neutral to obtain aminophosphonic acid functionalized polyacrylonitrile fiber, and drying for later use; wherein the proportion of the aminated polyacrylonitrile fiber, the aldehydes and the phosphoric acid substances is 1g (10-30) ml (3-8).
2. The method of recovering gold in thiosulfate solution in accordance with claim 1, characterized in that: the mass of the added functional polyacrylonitrile fiber adsorbent is 0.01-0.2 g/L, and the gold content in the thiosulfate gold leaching solution is 2-10 kg/t.
3. The method of recovering gold in thiosulfate solution in accordance with claim 1, characterized in that: and (3) the organic amine reagent in the step (2) is a polyethylene polyamine containing amino and imino.
4. The method of recovering gold in thiosulfate solution in accordance with claim 3, characterized in that: the organic amine reagent in the step (2) is: one or a mixture of a plurality of diethylenetriamine, triethylene tetramine and tetraethylenepentamine in any proportion.
5. The method for recovering gold in thiosulfate solution according to any one of claims 1 to 4, characterized in that: the temperature range of the reflux reaction in the step (2) is 100-140 ℃, and the time is 2-8 h.
6. The method of recovering gold in thiosulfate solution in accordance with claim 1, characterized in that: and (3) the phosphoric acid substance is a mixture obtained by one or more of hypophosphorous acid, phosphorous acid and phosphoric acid according to any proportion.
7. The method of recovering gold in thiosulfate solution in accordance with claim 1, characterized in that: the aldehyde substance in the step (3) is one or a mixture of two of formaldehyde and acetaldehyde in any proportion.
8. The method of recovering gold in thiosulfate solution in accordance with any one of claims 1, 6, 7, characterized in that: the temperature range of the reflux reaction in the step (3) is 50-90 ℃, and the time is 2-8 h.
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