CN115583673B - Method for recycling ammonium chloroplatinate from alumina sand - Google Patents
Method for recycling ammonium chloroplatinate from alumina sand Download PDFInfo
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- CN115583673B CN115583673B CN202211194597.9A CN202211194597A CN115583673B CN 115583673 B CN115583673 B CN 115583673B CN 202211194597 A CN202211194597 A CN 202211194597A CN 115583673 B CN115583673 B CN 115583673B
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- platinum
- thiourea
- alumina
- alumina sand
- sand
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- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 title claims abstract description 59
- 239000004576 sand Substances 0.000 title claims abstract description 57
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 title claims abstract description 39
- 238000000034 method Methods 0.000 title claims abstract description 39
- 238000004064 recycling Methods 0.000 title abstract description 13
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical group [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims abstract description 210
- UMGDCJDMYOKAJW-UHFFFAOYSA-N thiourea Chemical compound NC(N)=S UMGDCJDMYOKAJW-UHFFFAOYSA-N 0.000 claims abstract description 114
- 229910052697 platinum Inorganic materials 0.000 claims abstract description 101
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims abstract description 60
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Natural products NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 claims abstract description 57
- 239000011347 resin Substances 0.000 claims abstract description 50
- 229920005989 resin Polymers 0.000 claims abstract description 50
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims abstract description 44
- NLXLAEXVIDQMFP-UHFFFAOYSA-N Ammonia chloride Chemical compound [NH4+].[Cl-] NLXLAEXVIDQMFP-UHFFFAOYSA-N 0.000 claims abstract description 38
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 33
- 238000002386 leaching Methods 0.000 claims abstract description 30
- 239000007788 liquid Substances 0.000 claims abstract description 29
- 239000002002 slurry Substances 0.000 claims abstract description 23
- 235000019270 ammonium chloride Nutrition 0.000 claims abstract description 19
- 238000010438 heat treatment Methods 0.000 claims abstract description 17
- 238000002156 mixing Methods 0.000 claims abstract description 13
- 238000001179 sorption measurement Methods 0.000 claims abstract description 8
- 238000003795 desorption Methods 0.000 claims abstract description 6
- 238000007873 sieving Methods 0.000 claims abstract description 3
- 239000000243 solution Substances 0.000 claims description 30
- 239000011259 mixed solution Substances 0.000 claims description 8
- 238000011049 filling Methods 0.000 claims description 7
- 238000004321 preservation Methods 0.000 claims description 5
- 231100000252 nontoxic Toxicity 0.000 abstract description 5
- 230000003000 nontoxic effect Effects 0.000 abstract description 5
- 239000010970 precious metal Substances 0.000 abstract description 4
- 229910000510 noble metal Inorganic materials 0.000 abstract description 3
- 230000009286 beneficial effect Effects 0.000 abstract description 2
- 238000004519 manufacturing process Methods 0.000 abstract 1
- 239000000047 product Substances 0.000 description 23
- 230000000052 comparative effect Effects 0.000 description 21
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 16
- 238000006243 chemical reaction Methods 0.000 description 12
- 238000011084 recovery Methods 0.000 description 12
- 239000002893 slag Substances 0.000 description 10
- 229910052782 aluminium Inorganic materials 0.000 description 8
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 8
- 239000012535 impurity Substances 0.000 description 8
- 229910052742 iron Inorganic materials 0.000 description 8
- 229910052725 zinc Inorganic materials 0.000 description 8
- 239000011701 zinc Substances 0.000 description 8
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 7
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 7
- 238000004458 analytical method Methods 0.000 description 7
- 229910052802 copper Inorganic materials 0.000 description 7
- 239000010949 copper Substances 0.000 description 7
- 229910052751 metal Inorganic materials 0.000 description 7
- 239000002184 metal Substances 0.000 description 7
- 229910052710 silicon Inorganic materials 0.000 description 7
- 239000010703 silicon Substances 0.000 description 7
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 6
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 6
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 6
- 238000001035 drying Methods 0.000 description 6
- 229910052749 magnesium Inorganic materials 0.000 description 6
- 239000011777 magnesium Substances 0.000 description 6
- 230000003647 oxidation Effects 0.000 description 6
- 238000007254 oxidation reaction Methods 0.000 description 6
- 230000008569 process Effects 0.000 description 6
- 239000007787 solid Substances 0.000 description 6
- 239000010936 titanium Substances 0.000 description 6
- 229910052719 titanium Inorganic materials 0.000 description 6
- 238000005303 weighing Methods 0.000 description 6
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 5
- 239000002699 waste material Substances 0.000 description 5
- 239000003054 catalyst Substances 0.000 description 4
- 229910021645 metal ion Inorganic materials 0.000 description 4
- 239000006228 supernatant Substances 0.000 description 4
- 239000002351 wastewater Substances 0.000 description 4
- 238000003723 Smelting Methods 0.000 description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 239000002253 acid Substances 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 230000007613 environmental effect Effects 0.000 description 3
- 150000002500 ions Chemical class 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- -1 platinum group metals Chemical class 0.000 description 3
- 238000005070 sampling Methods 0.000 description 3
- 238000005488 sandblasting Methods 0.000 description 3
- 238000000926 separation method Methods 0.000 description 3
- 238000003756 stirring Methods 0.000 description 3
- 238000009210 therapy by ultrasound Methods 0.000 description 3
- 239000002341 toxic gas Substances 0.000 description 3
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 2
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005265 energy consumption Methods 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 238000001556 precipitation Methods 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- LNAZSHAWQACDHT-XIYTZBAFSA-N (2r,3r,4s,5r,6s)-4,5-dimethoxy-2-(methoxymethyl)-3-[(2s,3r,4s,5r,6r)-3,4,5-trimethoxy-6-(methoxymethyl)oxan-2-yl]oxy-6-[(2r,3r,4s,5r,6r)-4,5,6-trimethoxy-2-(methoxymethyl)oxan-3-yl]oxyoxane Chemical compound CO[C@@H]1[C@@H](OC)[C@H](OC)[C@@H](COC)O[C@H]1O[C@H]1[C@H](OC)[C@@H](OC)[C@H](O[C@H]2[C@@H]([C@@H](OC)[C@H](OC)O[C@@H]2COC)OC)O[C@@H]1COC LNAZSHAWQACDHT-XIYTZBAFSA-N 0.000 description 1
- BZSXEZOLBIJVQK-UHFFFAOYSA-N 2-methylsulfonylbenzoic acid Chemical compound CS(=O)(=O)C1=CC=CC=C1C(O)=O BZSXEZOLBIJVQK-UHFFFAOYSA-N 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229910002651 NO3 Inorganic materials 0.000 description 1
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 description 1
- 229910004298 SiO 2 Inorganic materials 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- UIIMBOGNXHQVGW-DEQYMQKBSA-M Sodium bicarbonate-14C Chemical compound [Na+].O[14C]([O-])=O UIIMBOGNXHQVGW-DEQYMQKBSA-M 0.000 description 1
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 1
- 229910010413 TiO 2 Inorganic materials 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- QZPSXPBJTPJTSZ-UHFFFAOYSA-N aqua regia Chemical compound Cl.O[N+]([O-])=O QZPSXPBJTPJTSZ-UHFFFAOYSA-N 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 239000010953 base metal Substances 0.000 description 1
- 229910021538 borax Inorganic materials 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 238000005119 centrifugation Methods 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 229910052593 corundum Inorganic materials 0.000 description 1
- 239000010431 corundum Substances 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 238000002354 inductively-coupled plasma atomic emission spectroscopy Methods 0.000 description 1
- 229920000609 methyl cellulose Polymers 0.000 description 1
- 239000001923 methylcellulose Substances 0.000 description 1
- 235000010981 methylcellulose Nutrition 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 238000000053 physical method Methods 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 230000001698 pyrogenic effect Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 229910052702 rhenium Inorganic materials 0.000 description 1
- WUAPFZMCVAUBPE-UHFFFAOYSA-N rhenium atom Chemical compound [Re] WUAPFZMCVAUBPE-UHFFFAOYSA-N 0.000 description 1
- 238000012216 screening Methods 0.000 description 1
- 238000007086 side reaction Methods 0.000 description 1
- 229910000029 sodium carbonate Inorganic materials 0.000 description 1
- 235000017550 sodium carbonate Nutrition 0.000 description 1
- 235000011121 sodium hydroxide Nutrition 0.000 description 1
- SUKJFIGYRHOWBL-UHFFFAOYSA-N sodium hypochlorite Chemical compound [Na+].Cl[O-] SUKJFIGYRHOWBL-UHFFFAOYSA-N 0.000 description 1
- PFUVRDFDKPNGAV-UHFFFAOYSA-N sodium peroxide Chemical compound [Na+].[Na+].[O-][O-] PFUVRDFDKPNGAV-UHFFFAOYSA-N 0.000 description 1
- 239000004328 sodium tetraborate Substances 0.000 description 1
- 235000010339 sodium tetraborate Nutrition 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G55/00—Compounds of ruthenium, rhodium, palladium, osmium, iridium, or platinum
- C01G55/002—Compounds containing, besides ruthenium, rhodium, palladium, osmium, iridium, or platinum, two or more other elements, with the exception of oxygen or hydrogen
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G55/00—Compounds of ruthenium, rhodium, palladium, osmium, iridium, or platinum
- C01G55/001—Preparation involving a liquid-liquid extraction, an adsorption or an ion-exchange
-
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Manufacture And Refinement Of Metals (AREA)
Abstract
The invention discloses a method for recycling ammonium chloroplatinate from alumina sand, and relates to the technical field of precious metal recycling; the method for recycling ammonium chloroplatinate from alumina sand provided by the invention comprises the following steps: (1) Uniformly mixing alumina sand and water, and then sieving with an ultrasonic water sieve to obtain an oversize product and an undersize product, wherein the oversize product is alumina coarse sand, and the undersize product is platinum enriched slurry; (2) Mixing the platinum enrichment slurry with hydrochloric acid, heating for the first time, adding hydrogen peroxide, heating for the second time, preserving heat, and centrifuging to obtain leaching residues and leaching liquid; (3) The leaching solution is subjected to adsorption saturation by three-stage series thiourea resin, and then desorption is carried out to obtain platinum solution; (4) Uniformly mixing the platinum liquid and ammonium chloride, and reacting to obtain ammonium chloroplatinate; the method provided by the invention can realize the short-process, non-toxic and high-yield recycling of the noble metal platinum, is simple to operate, and is beneficial to actual production.
Description
Technical Field
The invention relates to the technical field of precious metal recovery, in particular to a method for recovering ammonium chloroplatinate from alumina sand.
Background
Platinum is an important strategic precious metal resource, and platinum metal has a series of unique physical and chemical properties such as high melting point, high temperature oxidation resistance, corrosion resistance, excellent conductivity, high catalytic activity, selectivity and the like, and is widely applied to the fields of automobile industry, jewelry handkerchief, finance industry, high-end weapon, petrochemical industry, electronic industry, glass industry, medicine and health, energy and environmental protection and the like. In the back end application process, a precious metal platinum layer is sputtered and sprayed on a baffle plate, and according to the situation, most of the platinum layer is stripped by a physical method such as a stripping tool, and the rest of platinum is stripped by a sand blaster. The sand blasting is mainly white corundum, sand sprayed from a sand blaster at high speed impacts a platinum layer on the baffle plate, a small amount of platinum is stripped from the platinum layer, and the baffle plate is returned for use. The aluminum oxide sand containing platinum is formed after sand blasting is repeatedly used for a plurality of times, and the main component is alpha-Al 2 O 3 ：99％，SiO 2 ：0.20％，Fe 2 O 3 ：0.1％，TiO 2 :0.05%, mgO:0.1%, cu:0.003 percent, 0.0015 percent of Zn and 150 to 600ppm of Pt. The platinum content in the alumina sand is notHigh, but because platinum metal is scarce in yield in nature and expensive, secondary recovery is necessary. Due to alpha-Al in alumina sand 2 O 3 The properties are very stable, the platinum content is very low, the extraction difficulty is high, and the environment-friendly, economic and efficient recovery method is required to be continuously researched.
The invention patent (CN 201810979537.5) aims at the waste catalyst of platinum and rhenium of an alumina carrier, firstly, roasting and removing carbon and organic matters, then, dissolving the alumina carrier by sulfuric acid, and then, dissolving platinum by aqua regia and removing nitrate, thereby consuming a large amount of sulfuric acid and waste water with heavy environmental burden. The invention patent (CN 201710383466.8) firstly carries out roasting transformation, crushing and grinding on the alumina carrier, then adopts hydrochloric acid, sulfuric acid, naCl and liquid NaClO 3 Dissolving platinum. Whereas the invention patent (CN 201810842524.3) is directed to poorly soluble alpha-Al 2 O 3 Based on the platinum-containing dead catalyst, discloses double-alkali roasting-water leaching to dissolve Al 2 O 3 And (3) oxidizing and dissolving the platinum by using hydrochloric acid and sodium chlorate. The method generates a large amount of wastewater, and the platinum group metal dissolving process is easy to generate NOx or Cl 2 And toxic gases such as ammonia, and serious environmental pollution. The invention patent (CN 201710856842.0) discloses a method for capturing platinum group metals by microwave heating and melting, ni 3 S 2 Adding at least one of borax, sodium carbonate, sodium bicarbonate, sodium hydroxide, sodium peroxide and methyl cellulose to form slag as trapping agent, and microwave trapping the platinum group metal in the waste catalyst at 1050-1200 deg.c 2 Is a toxic gas and has a certain environmental risk. The invention patent (CN 202010835163.7) discloses a method for enriching platinum group metals in an aluminum-based waste catalyst by adopting CaO-Al 2 O 3 -Fe 2 O 3 -B 2 O 3 Slag smelting, the smelting temperature is 1500-1800 ℃, and the smelting temperature and the energy consumption are high.
Aiming at the technical problems of long flow, difficult treatment of waste water, generation of toxic gas, high temperature, high energy consumption and the like in the prior art in a wet method for recovering platinum metal from platinum-containing alumina materials, the method for recovering platinum metal in the prior art is needed to be searched.
Disclosure of Invention
Based on this, the present invention aims to overcome the above-mentioned disadvantages of the prior art and provide a short-flow, non-toxic and high-yield method for recovering ammonium chloroplatinate from alumina sand.
In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: a method for recovering ammonium chloroplatinate from alumina sand, comprising the steps of:
(1) Uniformly mixing alumina sand and water, and then sieving with an ultrasonic water sieve to obtain an oversize product and an undersize product, wherein the oversize product is alumina coarse sand, and the undersize product is platinum enriched slurry;
(2) Mixing the platinum enrichment slurry with hydrochloric acid, heating for the first time, adding hydrogen peroxide, heating for the second time, preserving heat, and centrifuging to obtain leaching residues and leaching liquid;
(3) The leaching solution is subjected to adsorption saturation by three-stage series thiourea resin, and then desorption is carried out to obtain platinum solution;
(4) And uniformly mixing the platinum liquid and ammonium chloride, and reacting to obtain the ammonium chloroplatinate.
The invention provides a method for recycling and preparing ammonium chloroplatinate from alumina sand, which is characterized in that high-purity platinum liquid is obtained through ultrasonic water screen, hydrochloric acid and hydrogen peroxide oxidation acid leaching and resin adsorption and desorption, and the ammonium chloroplatinate is further prepared, so that the short-flow, non-toxic and high-yield recycling of noble metal platinum is realized.
Preferably, in the step (1), the mass ratio of the alumina sand to the water is that of the alumina sand: water = 1: (1-2); the vibration time of the ultrasonic water screen is 30-50min, and the mesh number of the ultrasonic water screen is more than or equal to 200 meshes.
In the practical experiment process, the hardness and the particle size of the alumina sand are large, and the platinum mixed in the impact baffle plate in the sand blasting process exists in a very fine powder state, so that the density of the alumina is also higher than that of the platinum powder. In consideration of the actual situation, the invention utilizes the difference of physical properties, does not need complex equipment and flow to carry out pyrogenic enrichment, uses an ultrasonic water screen, is not easy to generate dust compared with the conventional screening, and is more thoroughly separated. The surplus water in the slurry can be returned to the next batch for use, thereby further reducing the amount of wastewater.
Preferably, in the step (1), after obtaining the undersize product, still standing and settling the undersize product to obtain a supernatant and a undersize product, wherein the undersize product is a platinum enriched slurry.
Preferably, in the step (2), the mass fraction of the hydrochloric acid is 31-36%, and the hydrochloric acid is heated to 60-70 ℃ for the first time; the mass fraction of the hydrogen peroxide is 50%, the mass percentage of the hydrogen peroxide relative to the platinum enriched slurry is 20-40%, the second heating is carried out to 80-90 ℃, and the heat preservation is carried out for 3-6h.
The invention adopts hydrochloric acid and hydrogen peroxide to dissolve platinum, and the main reaction is 6HCl+Pt+2H 2 O 2 ＝H 2 PtCl 6 +4H 2 O, side reaction 2H 2 O 2 ＝2H 2 O+O 2 The byproducts are water and oxygen, so that the method is nontoxic, the alumina basically does not participate in the reaction, and only a very small amount of base metal enters the leaching solution, so that the difficulty of purifying platinum is reduced. The leaching slag obtained by the centrifugation is alpha-Al 2 O 3 Platinum and a small amount of impurities such as aluminum, iron, copper, zinc, silicon and the like enter the leaching solution; in addition, the mass percentage of the hydrogen peroxide relative to the platinum enriched slurry is 20-40%, and when the heating temperature is within the range of the invention, the excellent yield can be obtained, and the yield reduction caused by too little hydrogen peroxide addition or too low temperature, or the waste of raw materials and energy sources caused by too much hydrogen peroxide addition or too high temperature can be avoided.
Preferably, in the step (2), the adding rate of the hydrogen peroxide is 10-15mL/min.
Preferably, in the step (3), the thiourea resin with three-stage cascade connection is prepared by adopting a cascade connection mode by thiourea resin columns, wherein the diameter of a single thiourea resin column is 25-30mm, the height of the single thiourea resin column is 300-500mm, and the filling amount of the thiourea resin in the single thiourea resin column is 50-70% of that of the thiourea resin column.
Preferably, in the step (3), the flow rate of the leachate passing through the thiourea resin in three stages in series is 1 to 6 times the filling amount of the thiourea resin per hour.
According to the invention, enrichment and purification are carried out through three-stage series thiourea resin, platinum ions are adsorbed completely, impurity metal ions are remained in the adsorbed liquid, the adsorbed liquid can be returned to be oxidized and leached, and the generation of waste acid water is reduced.
Preferably, in the step (3), the desorbed solution is a mixed solution of thiourea and hydrochloric acid, wherein the mass fraction of thiourea in the mixed solution is 3-8% and the mass fraction of hydrochloric acid is 4-11%; the volume ratio of the mixed solution of thiourea and hydrochloric acid to the thiourea resin is: thiourea resin= (1-2.5): 1.
preferably, in the step (4), the concentration of ammonium chloride in a system obtained by uniformly mixing and reacting the platinum liquid and the ammonium chloride is 10-20g/L.
In addition, the invention provides ammonium chloroplatinate recovered by the method for recovering ammonium chloroplatinate from alumina sand.
Compared with the prior art, the invention has the beneficial effects that: the invention provides a method for recycling and preparing ammonium chloroplatinate from alumina sand, which is characterized in that high-purity platinum liquid is obtained through ultrasonic water screen, hydrochloric acid and hydrogen peroxide oxidation acid leaching and resin adsorption and desorption, and the ammonium chloroplatinate is further prepared, so that the short-flow, non-toxic and high-yield recycling of noble metal platinum is realized.
Drawings
FIG. 1 is a process flow diagram of the present invention;
FIG. 2 is a schematic diagram of a three-stage series thiourea resin apparatus.
Detailed Description
For a better description of the objects, technical solutions and advantages of the present invention, the present invention will be further described with reference to the following specific examples. In the examples, the experimental methods used are conventional methods unless otherwise specified, and the materials, reagents, etc. used, unless otherwise specified, are commercially available.
Example 1
The invention discloses a method for recycling ammonium chloroplatinate from alumina sand, which is shown in a figure 1, and comprises the following steps:
(1) Weighing 36kg of alumina sand (with the platinum content of 600 ppm) and 40kg of pure water, uniformly mixing (the alumina sand is water=1:1.11), then passing through a 200-mesh ultrasonic water sieve, carrying out ultrasonic treatment for 30min to obtain an oversize product and an undersize product, wherein the oversize product is alumina coarse sand, the drying weight is 33.3kg, the platinum content is detected to be less than 1ppm, the undersize product is a coarse platinum enrichment slurry containing a small amount of alumina fine sand, standing and settling the platinum enrichment slurry, returning supernatant to the next batch, and obtaining the undersize product which is the platinum enrichment slurry with the platinum content being detected to be enriched to 8000ppm;
(2) Weighing 1.35kg of platinum enriched slurry, adding 1.5L of pure water, stirring at a rotating speed of 400r/min, adding 2L of hydrochloric acid with a mass fraction of 36%, heating to 65 ℃, adding 540g of hydrogen peroxide with a mass fraction of 50% at a rate of 15mL/min, continuously heating to 90 ℃, carrying out heat preservation reaction for 4 hours, carrying out solid-liquid separation to obtain 1.338kg of leached slag, detecting that the platinum content in the leached slag is less than 1ppm, detecting that the platinum content in the leached slag is 2915ppm, 123ppm of aluminum, 87ppm of iron, 10ppm of copper, 4ppm of zinc, 35ppm of silicon, 13ppm of titanium and 26ppm of magnesium, and calculating that the leaching rate of platinum is 99.87%;
(3) 3.7L of the leaching solution is adsorbed through 150mL of thiourea resin (the structure schematic diagram of the thiourea resin is shown in figure 2) in three stages in series at the rate of 900mL/h, wherein the diameter of a single thiourea resin column in the thiourea resin in the three stages in series is 25mm, the height is 400mm, and the filling amount of the thiourea resin in the single thiourea resin column is 60% of that in the thiourea resin column; sampling and inspecting the absorbed liquid, detecting 0.2ppm of platinum, 122ppm of aluminum, 86ppm of iron, 10ppm of copper, 4ppm of zinc, 35ppm of silicon, 13ppm of titanium and 26ppm of magnesium, and keeping impurity metal ions in the absorbed liquid, and collecting the absorbed liquid in a concentrated way and returning to the next batch of oxidation leaching; after the adsorption is finished, using thiourea with the mass fraction of 5% and hydrochloric acid with the mass fraction of 8% as an analysis solution to analyze, wherein the volume of the analysis solution is 1.5 times of the volume of the resin, so as to obtain platinum solution with the platinum content of 17g/L, and detecting the rest metal impurity ions to be less than 1ppm;
(4) And adding 6.4g of analytically pure ammonium chloride solid into 300mL of platinum solution, reacting for 60min, after the reaction is finished, obtaining 11.6g of ammonium chloroplatinate solid by centrifugal drying, wherein the mass concentration of ammonium chloride in the system is 12 g/L.
Example 2
The invention discloses a method for recycling ammonium chloroplatinate from alumina sand, which comprises the following steps:
(1) Weighing 36kg of alumina sand (with the platinum content of 150 ppm) and 40kg of pure water, uniformly mixing (the alumina sand is water=1:1.11), then passing through a 200-mesh ultrasonic water sieve, and carrying out ultrasonic treatment for 40min to obtain an oversize product and an undersize product, wherein the oversize product is alumina coarse sand, the drying weight is 34.92kg, the platinum content is detected to be less than 1ppm, the undersize product is a coarse platinum enrichment slurry containing a small amount of alumina fine sand, standing and settling the platinum enrichment slurry, returning supernatant to the next batch, and the undersize product is the platinum enrichment slurry, and the platinum content is detected to be enriched to 5000ppm;
(2) Weighing 1.08kg of platinum enriched slurry, adding 1.2L of pure water, stirring at a rotating speed of 300r/min, adding 1.6L of hydrochloric acid with a mass fraction of 36%, heating to 60 ℃, adding 432g of hydrogen peroxide with a mass fraction of 50% at a rate of 10mL/min, continuously heating to 90 ℃, carrying out heat preservation reaction for 6 hours, carrying out solid-liquid separation to obtain 1.074kg of leached slag after the reaction is finished, detecting that the platinum content in the leached slag is less than 1ppm, detecting that the leaching liquid is 2.9L, detecting that the platinum content in the leaching liquid is 1860ppm, 103ppm of aluminum, 65ppm of iron, 9ppm of copper, 3ppm of zinc, 29ppm of silicon, 11ppm of titanium and 23ppm of magnesium, and calculating that the leaching rate of platinum is 99.89%;
(3) Adsorbing 2.9L of the leaching solution at a rate of 750mL/h through 150mL of thiourea resin in three-stage cascade connection, wherein the diameter of a single thiourea resin column in the thiourea resin in the three-stage cascade connection is 25mm, the height is 400mm, and the filling amount of the thiourea resin in the single thiourea resin column is 60% of that of the thiourea resin column; sampling and inspecting the absorbed liquid, detecting 0.3ppm of platinum, 102ppm of aluminum, 63ppm of iron, 9ppm of copper, 3ppm of zinc, 28ppm of silicon, 11ppm of titanium and 23ppm of magnesium, and keeping impurity metal ions in the absorbed liquid, and collecting the absorbed liquid in a concentrated way and returning to the next batch of oxidation leaching; after the adsorption is finished, using thiourea with the mass fraction of 6% and hydrochloric acid mixed solution with the mass fraction of 11% as an analysis solution to analyze, wherein the volume of the analysis solution is 2 times of the volume of the resin, so as to obtain platinum solution with the platinum content of 13g/L, and detecting the rest metal impurity ions to be less than 1ppm;
(4) And adding 5.0g of analytically pure ammonium chloride solid into 200mL of platinum solution, reacting for 60min, after the reaction is finished, obtaining 5.92g of ammonium chloroplatinate solid by centrifugal drying, wherein the mass concentration of ammonium chloride in the system is 18 g/L.
Example 3
The invention discloses a method for recycling ammonium chloroplatinate from alumina sand, which comprises the following steps:
(1) Weighing 36kg of alumina sand (with the platinum content of 400 ppm) and 40kg of pure water, uniformly mixing (the alumina sand is water=1:1.11), then passing through a 200-mesh ultrasonic water sieve, and carrying out ultrasonic treatment for 45min to obtain an oversize product and an undersize product, wherein the oversize product is alumina coarse sand, the drying weight is 34.5kg, the platinum content is detected to be less than 1ppm, the undersize product is a coarse platinum enrichment slurry containing a small amount of alumina fine sand, standing and settling the platinum enrichment slurry, returning supernatant to the next batch, and obtaining the undersize product which is the platinum enrichment slurry with the platinum content being detected to be enriched to 6200ppm;
(2) Weighing 1.5kg of platinum enriched slurry, adding 1.67L of pure water, stirring at a rotating speed of 350r/min, adding 2.23L of hydrochloric acid with a mass fraction of 36%, heating to 70 ℃, adding 600g of hydrogen peroxide with a mass fraction of 50% at a rate of 12.5mL/min, continuously heating to 90 ℃, carrying out heat preservation reaction for 5 hours, carrying out solid-liquid separation to obtain 1.490kg of leaching slag after the reaction is finished, detecting that the platinum content in the leaching slag is less than 1ppm, detecting that the leaching liquid is 3.95L, detecting that the platinum content in the leaching liquid is 2353ppm, 93ppm of aluminum, 77ppm of iron, 8ppm of copper, 2ppm of zinc, 25ppm of silicon, 16ppm of titanium and 27ppm of magnesium, and calculating that the leaching rate of platinum is 99.93%;
(3) Adsorbing 3.95L of the leaching solution at a rate of 600mL/h through 150mL of thiourea resin in three-stage cascade connection, wherein the diameter of a single thiourea resin column in the thiourea resin in the three-stage cascade connection is 25mm, the height is 400mm, and the filling amount of the thiourea resin in the single thiourea resin column is 60% of that of the thiourea resin column; sampling and inspecting the absorbed liquid, detecting 0.1ppm of platinum, 92ppm of aluminum, 75ppm of iron, 8ppm of copper, 2ppm of zinc, 24ppm of silicon, 16ppm of titanium and 27ppm of magnesium, and keeping impurity metal ions in the absorbed liquid, and collecting the absorbed liquid in a concentrated way and returning to the next batch of oxidation leaching; after the adsorption is finished, using thiourea with the mass fraction of 8% and hydrochloric acid mixed solution with the mass fraction of 8% as an analysis solution to analyze, wherein the volume of the analysis solution is 1.5 times of the volume of the resin, so as to obtain platinum solution with the platinum content of 19g/L, and detecting the rest metal impurity ions to be less than 1ppm;
(4) And adding 10.2g of analytically pure ammonium chloride solid into 500mL of platinum solution, reacting for 60min, after the reaction is finished, obtaining 21.63g of ammonium chloroplatinate solid by centrifugal drying, wherein the mass concentration of ammonium chloride in the system is 10 g/L.
Example 4
The invention provides a method for recovering ammonium chloroplatinate from alumina sand, which is the only difference from the embodiment 1 in that 270g of hydrogen peroxide with the mass fraction of 50% is added at the rate of 15mL/min in the step (2).
Comparative example 1
This comparative example provides a method for recovering ammonium chloroplatinate from alumina sand, which differs from example 1 only in that 180g of hydrogen peroxide with a mass fraction of 50% is added at a rate of 15mL/min in step (2).
Comparative example 2
This comparative example provides a process for recovering ammonium chloroplatinate from alumina sand, which differs from example 1 only in that in step (2), the mass fraction of hydrochloric acid is 10%.
Comparative example 3
This comparative example provides a method for recovering ammonium chloroplatinate from alumina sand, which differs from example 1 only in that in step (2), hydrochloric acid is added, and hydrogen peroxide is added after heating to 45 ℃.
Comparative example 4
This comparative example provides a method for recovering ammonium chloroplatinate from alumina sand, which differs from example 1 only in that in step (3), the mass fraction of thiourea in the analytical solution is 12% and the mass fraction of hydrochloric acid is 20%.
Comparative example 5
This comparative example provides a method for recovering ammonium chloroplatinate from alumina sand, which differs from example 1 only in that in step (3), the mass fraction of thiourea in the analytical solution is 1% and the mass fraction of hydrochloric acid is 2%.
Comparative example 6
This comparative example provides a method for recovering ammonium chloroplatinate from alumina sand, which is the only difference from example 1 in that in step (4), the mass of ammonium chloride added is 3.2g, and after the reaction is completed, the mass concentration of ammonium chloride in the system is 1g/L.
Comparative example 7
This comparative example provides a method for recovering ammonium chloroplatinate from alumina sand, which is the only difference from example 1 in that in step (4), the mass of ammonium chloride added is 11.8g, and after the reaction is completed, the mass concentration of ammonium chloride in the system is 30g/L.
Effect example
This effect example the total recovery of ammonium chloroplatinate of examples 1 to 4 and comparative examples 1 to 7 was calculated from the mass of the finally obtained ammonium chloroplatinate and the content of platinum in the raw material, and the calculation method of the total recovery of platinum was: (mass of platinum in ammonium chloroplatinate/mass of platinum in original alumina sand) ×100%. The purity of the ammonium chloroplatinate was measured by ICP-OES, and the results are shown in Table 1;
TABLE 1
As can be seen from table 1, when the technical scheme of the present invention is adopted, the total recovery rate of the obtained platinum is above 99.4%, and the purity of the obtained ammonium chloroplatinate is greater than 4N;
as can be seen from example 1 and comparative example 1, when the hydrogen peroxide added in step (2) is too small, the recovery rate of platinum is significantly reduced; as can be seen from example 1 and comparative example 2, when the mass fraction of hydrochloric acid added in step (2) is too low, the recovery rate of platinum is also significantly reduced;
as can be seen from example 1 and comparative example 3, when the temperature at the time of adding hydrogen peroxide in step (2) is too low, the recovery rate of platinum is significantly lowered;
as can be seen from example 1 and comparative examples 4 to 5, when the mass fractions of thiourea and hydrochloric acid in the analytical solution are out of the ranges given in the present invention, the platinum analysis is not complete and the recovery rate of platinum is relatively low;
as can be seen from example 1 and comparative example 6, when the mass of ammonium chloride added during the platinum precipitation is too small, the recovery rate of platinum is significantly lowered; as can be seen from example 1 and comparative example 7, when the mass of ammonium chloride added during the platinum precipitation is excessive, the recovery rate of platinum is also reduced and the auxiliary materials are wasted.
Finally, it should be noted that the above embodiments are only for illustrating the technical solution of the present invention and not for limiting the scope of the present invention, and although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solution of the present invention may be modified or substituted equally without departing from the spirit and scope of the technical solution of the present invention.
Claims (4)
1. A method for recovering ammonium chloroplatinate from alumina sand, comprising the steps of:
(1) Uniformly mixing alumina sand and water, and then sieving with an ultrasonic water sieve to obtain an oversize product and an undersize product, wherein the oversize product is alumina coarse sand, and the undersize product is platinum enriched slurry;
(2) Mixing the platinum enrichment slurry with hydrochloric acid, heating for the first time, adding hydrogen peroxide, heating for the second time, preserving heat, and centrifuging to obtain leaching residues and leaching liquid;
(3) The leaching solution is subjected to adsorption saturation by three-stage series thiourea resin, and then desorption is carried out to obtain platinum solution; the desorption solution is mixed solution of thiourea and hydrochloric acid, wherein the mass fraction of the thiourea in the mixed solution is 3-8%, and the mass fraction of the hydrochloric acid is 4-11%;
(4) Uniformly mixing the platinum liquid and ammonium chloride, and reacting to obtain ammonium chloroplatinate;
in the step (1), the mass ratio of the alumina sand to the water is that the alumina sand: water = 1: (1-2); the vibration time of the ultrasonic water screen is 30-50min, and the mesh number of the ultrasonic water screen is more than or equal to 200 meshes;
in the step (2), the mass fraction of hydrochloric acid is 31-36%, and the hydrochloric acid is heated to 60-70 ℃ for the first time; the mass fraction of the hydrogen peroxide is 50%, the mass percentage of the hydrogen peroxide relative to the platinum enriched slurry is 20-40%, the second heating is carried out to 80-90 ℃, and the heat preservation is carried out for 3-6h;
in the step (4), the concentration of ammonium chloride in a system after the platinum liquid and the ammonium chloride are uniformly mixed and reacted is 10-20g/L;
the alumina sand is platinum-containing alumina sand.
2. The method for recovering ammonium chloroplatinate from alumina sand as defined in claim 1, wherein in the step (3), three-stage series connected thiourea resin is prepared by a series connection of thiourea resin columns, the diameter of a single thiourea resin column is 25-30mm, the height is 300-500mm, and the filling amount of thiourea resin in the single thiourea resin column is 50-70% of that in the thiourea resin column.
3. The method for recovering ammonium chloroplatinate from alumina sand of claim 2, wherein in step (3), the flow rate of the leachate passing through the three stages of thiourea resins in series is 1 to 6 times the filling amount of thiourea resin per hour.
4. The method for recovering ammonium chloroplatinate from alumina sand as defined in claim 1, wherein the volume ratio of the mixed solution of thiourea and hydrochloric acid to the thiourea resin is: thiourea resin= (1-2.5): 1.
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| RU2181659C2 (en) * | 2000-07-24 | 2002-04-27 | ОАО Верхнесалдинское металлургическое производственное объединение | Method of utilization and regeneration of medium in abrasive blasting processes |
| EP3115151A1 (en) * | 2015-07-07 | 2017-01-11 | STM Stein-Moser GmbH | Recovery of abrasive from abrasive - water jet - cutting installations |
| CN106480313A (en) * | 2015-09-02 | 2017-03-08 | 徐州北矿金属循环利用研究院 | Method for recovering platinum from indissolvable silicon-aluminum-based platinum-containing waste catalyst |
| CN114752760A (en) * | 2022-03-28 | 2022-07-15 | 北京科技大学 | Method for extracting gold and platinum group metal by utilizing selective biological adsorption |
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| US20040173057A1 (en) * | 2003-03-04 | 2004-09-09 | Aeromet Technologies, Inc. | Leach column and method for metal recovery |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| RU2181659C2 (en) * | 2000-07-24 | 2002-04-27 | ОАО Верхнесалдинское металлургическое производственное объединение | Method of utilization and regeneration of medium in abrasive blasting processes |
| EP3115151A1 (en) * | 2015-07-07 | 2017-01-11 | STM Stein-Moser GmbH | Recovery of abrasive from abrasive - water jet - cutting installations |
| CN106480313A (en) * | 2015-09-02 | 2017-03-08 | 徐州北矿金属循环利用研究院 | Method for recovering platinum from indissolvable silicon-aluminum-based platinum-containing waste catalyst |
| CN114752760A (en) * | 2022-03-28 | 2022-07-15 | 北京科技大学 | Method for extracting gold and platinum group metal by utilizing selective biological adsorption |
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