Abstract: A nickel recovering method includes: (A-i) a reduction heat treatment process for thermally treating a first raw material containing nickel and lithium; (B) a first leaching process for leaching the heat-treated product produced by the reduction heat treatment process; (A-ii) a first roasting process for thermally treating a second raw material containing nickel and sulfur; (C) a second leaching process for leaching the first leaching residue produced by the first leaching process and calcine produced by the first roasting process; (D) a neutralization process for neutralizing the second leachate produced by the second leaching process; (E) a purification process for removing impurities contained in the neutralized solution produced by the neutralization process; (F) a precipitation process for performing precipitation on the purified solution produced by the purification process; and (G) a second roasting process for roasting the precipitated residue produced by the precipitation process to recover nickel.

Abstract: Provided herein is a method for preparing a nickel sulfate aqueous solution, comprising: (A-i) a reduction heat treatment process for thermally treating a first raw material containing nickel and lithium; (B) a first leaching process for leaching the heat-treated product produced by the reduction heat treatment process; (A-ii) a roasting process for thermally treating a second raw material containing nickel and sulfur; (C) a second leaching process for leaching the first leaching residue produced by the first leaching process and the calcine produced by the roasting process; (D) a neutralization process for neutralizing the second leached solution produced by the second leaching process; and (E) a solvent extraction process for refining nickel in the neutralized solution produced by the neutralization process.

Abstract: Provided herein is a nickel recovering method, comprising: (A-i) a reduction heat treatment process for thermally treating a first raw material containing nickel and lithium; (B) a first leaching process for leaching the heat-treated product produced by the reduction heat treatment process; (A-ii) a roasting process for thermally treating a second raw material containing nickel and sulfur; (C) a second leaching process for leaching the first leaching residue produced by the first leaching process and calcine produced by the roasting process; (D) a neutralization process for neutralizing the second leachate produced by the second leaching process; (E) a purification process for removing impurities contained in the neutralized solution produced by the neutralization process; and (F) a precipitation process of performing a precipitation method to recover nickel from the purified solution produced by the purification process, and a nickel hydroxide is recovered by the precipitation process.

Abstract: Provided herein is a nickel recovering method, comprising: (A-i) a reduction heat treatment process for thermally treating a first raw material containing nickel and lithium; (B) a first leaching process for leaching the heat-treated product produced by the reduction heat treatment process; (A-ii) a roasting process for thermally treating a second raw material containing nickel and sulfur; (C) a second leaching process for leaching the first leaching residue produced by the first leaching process and calcine produced by the roasting process; (D) a neutralization process for neutralizing the second leachate produced by the second leaching process; (E) a purification process for removing impurities contained in the neutralized solution produced by the neutralization process; and (F) a reduction process for performing a hydrogen reduction method on the purified solution produced by the purification process to recover nickel from the purified solution.

Abstract: A method for producing a nickel sulfate solution includes a leaching step of leaching a nickel cathode in sulfuric acid under a high temperature and a high pressure to produce a leachate, a neutralization step of neutralizing the leachate produced in the leaching step to produce a neutralized solution, and a filtration step of filtering the neutralized solution produced in the neutralization step to produce a filtrate.

Abstract: A method for producing an aqueous solution containing nickel, cobalt and manganese, includes: a leaching process including a pressure-leaching process of leaching a raw material under pressure to form a leachate containing nickel, cobalt, manganese and impurities; an impurity removal process of removing the impurities from the leachate; a target substance precipitation process of precipitating a mixed hydroxide precipitate containing nickel, cobalt and manganese by introducing a neutralizing agent into a filtrate from which the impurities are removed; and a dissolution process. The pressure-leaching process includes a first-stage pressure-leaching process and a second-stage pressure-leaching process of pressure-leaching a residue of the first-stage pressure-leaching process with an acidity higher than an acidity in the first-stage pressure-leaching process.

Abstract: A method for producing an aqueous solution containing nickel or cobalt includes: (A) a leaching step, which includes a first atmospheric pressure heating leaching step and a second atmospheric pressure heating leaching step, in which a raw material is heated and leached under an atmospheric pressure to form a leachate solution containing nickel, cobalt, and impurities; (B) a first extraction step of separating the leachate solution into a first filtrate containing nickel and impurities and a first organic layer containing cobalt and impurities by adding a first solvent extractant to the leachate solution; (C-i) a precipitation removal step of precipitating and removing impurities including magnesium, calcium, or a mixture thereof by adding a precipitating agent to the first filtrate; and (D-i) a target material precipitation step of selectively precipitating a nickel cake containing nickel by adding a neutralizing agent to the first filtrate.