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CN-119082478-B - Ferronickel smelting method

CN119082478BCN 119082478 BCN119082478 BCN 119082478BCN-119082478-B

Abstract

The invention relates to a ferronickel smelting method, which comprises the following steps of carrying out acid leaching by oxidation to obtain leaching liquid and leaching slag, carrying out chromium removal on the obtained leaching liquid to obtain chromium-removed slag and chromium-removed filtrate, mixing a first oxidant, phosphoric acid and the obtained chromium-removed filtrate to carry out iron removal to obtain ferric phosphate and iron removal liquid, mixing ferric salt and the obtained iron removal liquid to carry out phosphorus removal to obtain phosphorus removal solution and iron phosphate slag, carrying out impurity removal on the obtained phosphorus removal solution, and using the obtained impurity removal liquid to prepare a ternary precursor. The method provided by the invention does not need extraction, reduces the treatment cost of the nickel-iron alloy, can also make the iron in the nickel-iron alloy into battery-grade ferric phosphate, and has higher comprehensive benefit because the nickel can be used for preparing the precursor.

Inventors

  • Ouyang Shibao
  • RUAN DINGSHAN
  • CHEN RUOKUI
  • RAO JINSHAN
  • LI CHANGDONG

Assignees

  • 广东邦普循环科技有限公司
  • 湖南邦普循环科技有限公司

Dates

Publication Date
20260505
Application Date
20240909

Claims (20)

  1. 1. A method for smelting ferronickel, the method comprising the steps of: (1) Firstly, mixing nickel-iron alloy with acid for acid leaching, and then adding hydrogen peroxide to a pH value of 1-2 to obtain leaching liquid and leaching slag; (2) Firstly, mixing a second oxidant with the leaching solution obtained in the step (1), then adding phosphate to perform a chromium removal reaction, standing, and then performing solid-liquid separation to obtain chromium removal slag and chromium removal filtrate; (3) Mixing a first oxidant, phosphoric acid and the chromium-removing filtrate obtained in the step (2) to remove iron so as to obtain ferric phosphate and iron-removing liquid; (4) Mixing ferric salt with the iron removing liquid obtained in the step (3) to remove phosphorus, so as to obtain a phosphorus removing solution and iron phosphate slag; (5) Concentrating the dephosphorization solution obtained in the step (4), mixing with silicate and alkali liquor, standing after the reaction, and carrying out solid-liquid separation to obtain impurity-removed slag and impurity-removed liquid, wherein the obtained impurity-removed liquid is used for preparing a precursor.
  2. 2. The method of claim 1, wherein the acid comprises any one or a combination of at least two of sulfuric acid, hydrochloric acid, or nitric acid.
  3. 3. The method of claim 2, wherein the acid is sulfuric acid.
  4. 4. The method of claim 1, wherein the acid is used in an amount greater than 0.8 times the theoretical amount.
  5. 5. The method of claim 1, wherein the acid leaching is at a temperature of 70 ℃ to 90 ℃.
  6. 6. The method of claim 1, wherein the acid leaching is for a time period of 2.5 to 5 hours.
  7. 7. The method of claim 1, wherein the second oxidant comprises any one or a combination of at least two of hydrogen peroxide, sodium persulfate, or manganese dioxide.
  8. 8. The method according to claim 1, wherein the second oxidant is added in an amount such that the ferric ion content in the system is 0.5g/L to 2g/L.
  9. 9. The method of claim 1, wherein the phosphate comprises any one or a combination of at least two of trisodium phosphate, sodium dihydrogen phosphate, or sodium monohydrogen phosphate.
  10. 10. The method according to claim 1, wherein the phosphate is added in an amount of 1.1 to 3 times the theoretical amount of chromium reaction in the system.
  11. 11. The method according to claim 1, wherein the temperature of the dechromization reaction is from 25 ℃ to 50 ℃.
  12. 12. The method according to claim 1, wherein the pH of the dechromization reaction is 3 to 5.
  13. 13. The method according to claim 1, wherein the time of the dechromization reaction is 1 to 3 hours.
  14. 14. The method of claim 1, wherein the time of the standing of step (2) is 5 to 12 hours.
  15. 15. The method of claim 1, wherein the first oxidant of step (3) comprises any one or a combination of at least two of hydrogen peroxide, oxygen, ozone, or sodium persulfate.
  16. 16. The method of claim 15, wherein the first oxidizing agent is hydrogen peroxide.
  17. 17. The method of claim 1, wherein the first oxidant is added in an amount of 1 to 1.5 times the theoretical amount of the reaction with the ferrous ions in the system.
  18. 18. The method according to claim 1, wherein the phosphoric acid is added in an amount of 1 to 1.2 times the theoretical amount of iron in the system.
  19. 19. The method according to claim 1, wherein the iron removal in step (3) is performed at a pH of 1 to 2.
  20. 20. The method according to claim 1, wherein the temperature of the iron removal in step (3) is 80 ℃ to 95 ℃.

Description

Ferronickel smelting method Technical Field The invention belongs to the technical field of valuable metal recovery, relates to an alloy smelting method, and particularly relates to a ferronickel smelting method. Background Nickel is used as a key material of a new energy power battery, is critical to the development of new energy automobiles, and the global production of nickel in minerals in 2023 is about 360 ten thousand tons according to statistics. The global nickel resource amount exceeds 3.5 hundred million gold tons, wherein 54 percent is laterite nickel ore, 35 percent is magma sulfide ore, 10 percent is blocky sulfide ore and 1 percent is tailings. The ferronickel alloy is an intermediate product in the smelting process of the nickel sulfide ore, and because the iron content in the ferronickel alloy is higher and the value of the iron is lower, the ferronickel alloy needs to be further smelted so as to enrich the nickel content in the ferronickel alloy into nickel beans or nickel powder with the nickel content of more than 90 percent. However, the process of converting the ferronickel alloy into nickel beans or nickel powder requires very high energy consumption, and iron in the ferronickel alloy can be buried as waste residues, so that the ferronickel alloy is not beneficial to effectively utilizing the iron in the ferronickel alloy. Along with the increasing demand of lithium iron phosphate batteries, the demand for iron resources is gradually increased, so that it is necessary to develop a recycling method of the nickel-iron alloy to realize the comprehensive utilization of nickel resources and iron resources in the nickel-iron alloy. Disclosure of Invention The invention aims to provide a ferronickel smelting method which can realize the purpose of deep impurity removal without extraction, can not only make iron in the ferronickel into battery-grade ferric phosphate, but also make nickel into a precursor, and has higher comprehensive benefit. In order to achieve the aim of the invention, the invention adopts the following technical scheme: The invention provides a ferronickel smelting method, which comprises the following steps: (1) Oxidizing and acid leaching the ferronickel alloy to obtain leaching liquid and leaching slag; (2) Removing chromium from the leaching solution obtained in the step (1) to obtain chromium-removed slag and chromium-removed filtrate; (3) Mixing a first oxidant, phosphoric acid and the chromium-removing filtrate obtained in the step (2) to remove iron so as to obtain ferric phosphate and iron-removing liquid; (4) Mixing ferric salt with the iron removing liquid obtained in the step (3) to remove phosphorus, so as to obtain a phosphorus removing solution and iron phosphate slag; (5) And (3) removing impurities from the phosphorus removal solution obtained in the step (4), wherein the obtained impurity removal solution is used for preparing a precursor. The method provided by the invention can realize the purpose of deep impurity removal without extraction operation, has lower treatment cost, can make iron in the nickel-iron alloy into battery-grade ferric phosphate, and can make nickel into a precursor, so that the comprehensive benefit is higher. Preferably, the oxidation acid leaching in step (1) comprises first mixing the nickel-iron alloy with an acid to perform acid leaching, and then adding hydrogen peroxide to a pH of 1 to 2, such as but not limited to 1, 1.2, 1.5, 1.8 or 2, and the remaining non-enumerated values within the numerical range are equally applicable, preferably 1.5 to 2. Preferably, the concentration of hydrogen peroxide used in the oxidation acid leaching process is 27.5wt% to 50wt%, for example, 27.5wt%, 30wt%, 35wt%, 40wt%, 45wt% or 50wt%, but is not limited to the recited values, and the remaining non-recited values within the range of values are equally applicable. Preferably, the acid comprises any one or a combination of at least two of sulfuric acid, hydrochloric acid or nitric acid, typically but not limited to a combination of sulfuric acid and hydrochloric acid, a combination of hydrochloric acid and nitric acid, a combination of sulfuric acid and nitric acid, or a combination of sulfuric acid, hydrochloric acid and nitric acid, preferably sulfuric acid. The concentration of sulfuric acid in the present invention is 70wt% or more, and may be, for example, 70wt%, 75wt%, 80wt%, 85wt%, 90wt%, 95wt% or 98wt%, but is not limited to the values recited, and the other values not recited in the numerical range are equally applicable. The amount of the acid is preferably 0.8 times or more the theoretical amount, and may be, for example, 0.8 times, 0.85 times, 0.9 times, 0.95 times or 1 time, but is not limited to the recited values, and the other non-recited values in the numerical range are equally applicable. If less acid is used in the oxidation acid leaching process, the content of Ni and Fe in the leaching solution is lower, and the subsequen