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CN-121759714-B - Method for preparing high-purity nickel cobalt by utilizing nickel cobalt sulfide slag

CN121759714BCN 121759714 BCN121759714 BCN 121759714BCN-121759714-B

Abstract

The invention relates to the technical field of recycling of metallurgical waste residues, in particular to a method for preparing high-purity nickel cobalt by utilizing nickel cobalt sulfide residues. The method for preparing high-purity nickel and cobalt by utilizing the nickel and cobalt sulfide slag comprises the following steps of S11 conveying the nickel and cobalt sulfide slag into a ball mill for crushing, screening to obtain nickel and cobalt sulfide slag powder, S12 roasting at a low temperature, S13, acid leaching, S14, removing Cu by replacement, S15, removing Zn, S16, extracting and back extracting, and S17, electrodepositing to obtain high-purity nickel and cobalt. The invention adopts the green low-temperature roasting, multi-stage purifying and impurity removing and electrowinning technology to obtain the high-purity nickel cobalt, has the advantages of low cost, green and environment-friendly property, high nickel cobalt recovery rate, high production efficiency and the like, and has great significance on the technology for preparing the high-purity nickel cobalt by industrially and comprehensively recycling the nickel cobalt sulfide slag.

Inventors

  • YANG HUI
  • LUO CHUNHUA
  • QIN RUYONG
  • HUANG YIFENG
  • XIAO PENG
  • ZHONG LINGQIANG
  • LONG WEIMING
  • XIA WEI
  • ZHONG CHANGMING

Assignees

  • 赣州寒锐新能源科技有限公司

Dates

Publication Date
20260508
Application Date
20260304

Claims (9)

  1. 1. The method for preparing the high-purity nickel cobalt by utilizing the nickel cobalt sulfide slag is characterized by comprising the following steps of: S11, conveying nickel-cobalt sulfide slag into a ball mill for crushing, and screening to obtain nickel-cobalt sulfide slag powder, wherein the granularity of the nickel-cobalt sulfide slag powder is 50-500 meshes; S12, uniformly mixing the nickel-cobalt sulfide slag powder obtained in the step S11 with sodium carbonate, silicon carbide and ferric oxide, and roasting at a low temperature to obtain a roasting product; s13, carrying out acid leaching on the roasting product obtained in the step S12 to obtain a crude nickel cobalt sulfate solution; s14, adding waste electrodeposited nickel leftover materials into the crude nickel cobalt sulfate solution obtained in the step S13 to replace and remove Cu, and filtering to obtain Cu-removed liquid; S15, adjusting the pH value of the Cu-removed liquid obtained in the step S14, removing Zn, and filtering to obtain Zn-removed liquid; S16, extracting the Zn-removed liquid obtained in the step S15 by using a solvent, wherein Co enters the solvent, ni is remained in the raffinate to obtain a high-purity nickel sulfate solution, and the solvent is subjected to back extraction by using a back extraction solvent to obtain a high-purity cobalt sulfate solution; s17, respectively removing oil from the high-purity nickel sulfate solution and the high-purity cobalt sulfate solution obtained in the step S16, and respectively carrying out electrodeposition to obtain high-purity nickel and cobalt, wherein the voltage in the electrodeposition process is 2-4V, and the electrodeposition time is 48-96 h.
  2. 2. The method for preparing high-purity nickel and cobalt by utilizing nickel and cobalt sulfide slag according to claim 1, wherein the mixture before low-temperature roasting in the step S12 comprises microwave activation treatment, the microwave frequency of the microwave activation treatment is 2450MHz, the power density is 1-3 kW/kg, the treatment time is 10-20 min, and the treatment temperature is 150-250 ℃.
  3. 3. The method for preparing high-purity nickel cobalt by utilizing nickel cobalt sulfide slag according to claim 1, wherein the acid leaching process in the step S13 is as follows: s21, leaching the roasting product in the step S12 by using 1.0mol/L methane sulfonic acid solution, wherein the liquid-solid ratio is 2-3:1, the leaching temperature is 50 ℃, the leaching time is 30min, and the leaching end point pH value is 0-2.0, so as to obtain a primary leaching solution; S22, adding concentrated sulfuric acid into the primary leaching solution obtained in the step S21, enabling the concentration of the sulfuric acid to reach 2.0mol/L, raising the temperature to 80 ℃, continuing to react for 1.5h, and filtering to obtain a crude nickel cobalt sulfate solution at the end point pH value of 0-1.0.
  4. 4. The method for preparing high-purity nickel and cobalt by utilizing nickel and cobalt sulfide slag according to claim 1, wherein nano copper powder seed crystals accounting for 5-10% of the silicon carbide mass are added in the process of replacing and removing copper in the step S14, and the granularity of the nano copper powder is 10-50 nm.
  5. 5. The method for preparing high-purity nickel and cobalt by utilizing nickel sulfide cobalt slag according to claim 1, wherein the addition amount of waste electrodeposited nickel leftover materials in the step S14 is 1.1-2 times of the theoretical amount, the reaction temperature is 20-30 ℃, and the reaction time is 10-60min.
  6. 6. The method for preparing high-purity nickel and cobalt by utilizing nickel and cobalt sulfide slag according to claim 1, wherein in the step S15, the pH value of the reaction solution is adjusted to be 5-5.5, the reaction time is 5-30 min, and the pH value is adjusted by sodium carbonate.
  7. 7. The method for preparing high-purity nickel and cobalt by utilizing nickel and cobalt sulfide slag according to claim 1, wherein sodium bicarbonate and sodium sulfite are added in the step S16 of extraction, on-line pH control is not needed, and the pH of the solution is stabilized between 4.7 and 5 in 8-hour continuous operation, so that the cobalt extraction rate is improved.
  8. 8. The method for preparing high-purity nickel and cobalt by utilizing nickel and cobalt sulfide slag according to claim 1, wherein in the step S16, the solvent is P507, the counter solvent is a eutectic solvent consisting of sulfuric acid or menthol and lactic acid in a molar ratio of 1:2, the preparation method of the eutectic solvent comprises the steps of stirring and mixing menthol and lactic acid in a molar ratio of 1:2 at a temperature of 28-30 ℃ for 30-60 min until uniform transparent liquid is formed, and dehydrating to obtain the eutectic solvent.
  9. 9. The method for preparing high-purity nickel cobalt by utilizing nickel cobalt sulfide slag according to claim 1, wherein the volume ratio of the Zn-removed liquid, the solvent and the counter solvent in the step S16 is (3-5): 1-2): 0.3-0.5.

Description

Method for preparing high-purity nickel cobalt by utilizing nickel cobalt sulfide slag Technical Field The invention relates to the technical field of recycling of metallurgical waste residues, in particular to a method for preparing high-purity nickel cobalt by utilizing nickel cobalt sulfide residues. Background With the explosive growth of new energy automobiles and consumer electronics industry, nickel and cobalt are used as core strategic metal resources, and the demands thereof are continuously rising. However, raw mineral resources are increasingly depleted and have high external dependencies. Meanwhile, in industrial links such as nickel cobalt wet smelting, electroplating, battery material production and the like, sodium sulfide or sodium hydrosulfide precipitation method is often adopted to treat nickel cobalt-containing wastewater to generate a large amount of nickel cobalt sulfide slag, the nickel cobalt sulfide slag contains toxic heavy metals and is easy to generate toxic hydrogen sulfide gas, in addition, the metal content in the nickel cobalt sulfide slag is higher, higher recovery value exists, and if the nickel cobalt sulfide slag is improperly treated, the surrounding environment is polluted, and resource waste is caused. The current treatment technology of the sulfation slag has the following technical bottlenecks and industry pain points: high energy consumption and low value of pyrogenic process CN108611493a discloses a comprehensive recovery method of sulfuration slag, which adopts mechanically activated sulfuration slag, solid sodium hydroxide and reducing carbon powder to mix and bake, and then obtains metal products and sodium sulfide solution through water dissolution. The metal product obtained by the method has low purity, can not effectively separate various metal elements, and has low added value. The problems of long flow and poor selectivity of wet process CN107012337a discloses a method for enriching and recovering nickel and cobalt from manganese-containing waste, which comprises the following steps of pulping manganese-containing waste sulfation slag, adding acid liquor into the sulfation slag, stirring and filtering, reslurrying the obtained acid-washing waste slag, adding an oxidant and the acid liquor, controlling the reaction temperature and the reaction pH value, carrying out a first stirring reaction, adding an alkali solution to adjust the pH value after the reaction is completed, carrying out a second stirring reaction, filtering, adjusting the pH value to be acidic in the obtained nickel-cobalt mixed liquor, adding sulfide again to precipitate and filtering, and obtaining nickel-cobalt-containing enriched slag and supernatant which can be returned to a manganese sulfate production line. The route has the technical problem of poor leaching selectivity. CN114212806a discloses a method for recovering nickel-cobalt-manganese sulfide slag, which oxidizes nickel-cobalt sulfide slag by using an oxidant, precipitates sodium hydroxide, and filters the acid solution to obtain nickel-cobalt-manganese sulfate solution. The method also only coarsely recovers nickel and cobalt, cannot finely separate metals, and has high metal loss rate. Technical barrier to the stability of the sulphide phases The nickel cobalt in the nickel cobalt sulfide slag mainly exists in NiS, coS, niS 2、Co3S4 and other forms, the crystal lattice is stable, and the dissolution dynamics is extremely poor under the conventional low-acid or non-oxidation condition. If the structure of the vulcanized phase is not thoroughly destroyed, the leaching rate is difficult to break through 90 percent. Therefore, there is a need in the art for a method for treating nickel-cobalt sulfide slag that can effectively separate nickel-cobalt metals, and has high recovery rate and environmental protection. Disclosure of Invention Aiming at the problems in the prior art, the invention provides a method for preparing high-purity nickel cobalt by utilizing nickel cobalt sulfide slag, and the method can be used for obtaining high-purity nickel sulfate and cobalt sulfate solution, and the prepared high-purity nickel cobalt plate has high purity and smooth surface and does not have the phenomena of air holes, edge warping, cracks and the like. The invention provides a method for preparing high-purity nickel cobalt by utilizing nickel cobalt sulfide slag, which comprises the following steps: S11, conveying nickel-cobalt sulfide slag into a ball mill for crushing, and screening to obtain nickel-cobalt sulfide slag powder, wherein the granularity of the nickel-cobalt sulfide slag powder is 50-500 meshes; S12, uniformly mixing the nickel-cobalt sulfide slag powder obtained in the step S11 with sodium carbonate, silicon carbide and ferric oxide, and roasting at a low temperature to obtain a roasting product; s13, carrying out acid leaching on the roasting product obtained in the step S12 to obtain a crude nickel cobalt sulfate solutio