A process and method for producing a crystallized metal sulfate. The crystallized metal sulfate may be battery-grade. The method may comprise receiving a metal ion-containing stream and crystalizing a metal sulfate from the stream. The process may comprise receiving a stream from a metal processing plant, and crystalizing a metal sulfate from the stream. The process may be a metal electrowinning process comprising crystalizing a metal ion-containing stream to form a crystallized metal sulfate in a mother liquor. The process or method may comprise returning the mother liquor upstream or to the metal electrowinning process.

A process and method for producing a crystallized metal sulfate. The crystallized metal sulfate may be battery-grade. The method may comprise receiving a metal ion-containing stream and crystalizing a metal sulfate from the stream. The process may comprise receiving a stream from a metal processing plant, and crystalizing a metal sulfate from the stream. The process may be a metal electrowinning process comprising crystalizing a metal ion-containing stream to form a crystallized metal sulfate in a mother liquor. The process or method may comprise returning the mother liquor upstream or to the metal electrowinning process.

A treatment process for crystallizing a metal sulfate involving pre-treating a feedstock comprising calcium, magnesium, and/or lithium impurities, the pre-treating involving pre-leaching the feedstock in the presence of a lixiviant, selectively extracting a first portion of any of the impurities from the feedstock, and forming a leached solution comprising an uncrystallized metal sulfate and any remaining impurities; and/or refining the leached solution and removing a second portion of any of the remaining impurities; and crystallizing the uncrystallized metal sulfate from the leached solution to form a crystallized metal sulfate. So processed, the crystallized metal sulfate may be battery-grade or electroplating-grade.

A process for removing impurities from a crystallized metal sulfate, including contacting crystallized metal sulfate with a liquor rich in metal sulfate. The metal may be cobalt, nickel, or manganese, and the impurities may be magnesium or calcium. The liquor rich in metal sulfate may be an overflow liquor from crystallization of the metal sulfate, and said overflow liquor may be subject to one or more impurities removal steps prior to contacting the crystallized metal sulfate, such that the overflow liquor contains lower levels of impurities than the crystallized metal sulfate to be contacted. A counter-current wash circuit may be used to remove impurities from a crystallized metal sulfate, whereby a plurality of washing tanks are configured to receive crystallized metal sulfate in a sequence, and washing liquor in reverse of said sequence.

A process for removing impurities from a crystallized metal sulfate, including contacting crystallized metal sulfate with a liquor rich in metal sulfate. The metal may be cobalt, nickel, or manganese, and the impurities may be magnesium or calcium. The liquor rich in metal sulfate may be an overflow liquor from crystallization of the metal sulfate, and said overflow liquor may be subject to one or more impurities removal steps prior to contacting the crystallized metal sulfate, such that the overflow liquor contains lower levels of impurities than the crystallized metal sulfate to be contacted. A counter-current wash circuit may be used to remove impurities from a crystallized metal sulfate, whereby a plurality of washing tanks are configured to receive crystallized metal sulfate in a sequence, and washing liquor in reverse of said sequence.

Disclosed is a method for producing battery-grade nickel sulfate by using laterite nickel ore comprising the following steps: sorting the laterite nickel ore to obtain lump ore and sediment ore; crushing the lump ore, and then performing heap leaching, to obtain a crude nickel sulfate solution A; separating the sediment ore to obtain high chromium ore, low iron, high magnesium ore, and high iron, low magnesium ore, and drying, roasting, reducing, and sulfurating the low iron, high magnesium ore to obtain low nickel matte; blowing and performing water extraction on the low nickel matte, and then performing oxygen pressure leaching, to obtain a crude nickel sulfate solution B; performing pressure leaching on the high iron, low magnesium ore to obtain a crude nickel sulfate solution C; and performing extraction on the crude nickel sulfate solutions A, B, and C, and then evaporating and crystallizing, to obtain battery-grade nickel sulfate.

Disclosed is a method for producing battery-grade nickel sulfate by using laterite nickel ore comprising the following steps: sorting the laterite nickel ore to obtain lump ore and sediment ore; crushing the lump ore, and then performing heap leaching, to obtain a crude nickel sulfate solution A; separating the sediment ore to obtain high chromium ore, low iron, high magnesium ore, and high iron, low magnesium ore, and drying, roasting, reducing, and sulfurating the low iron, high magnesium ore to obtain low nickel matte; blowing and performing water extraction on the low nickel matte, and then performing oxygen pressure leaching, to obtain a crude nickel sulfate solution B; performing pressure leaching on the high iron, low magnesium ore to obtain a crude nickel sulfate solution C; and performing extraction on the crude nickel sulfate solutions A, B, and C, and then evaporating and crystallizing, to obtain battery-grade nickel sulfate.

The present disclosure provides: a method for preparing a cathode active material precursor material by using a high-nickel-content waste lithium secondary battery; a method for preparing a cathode active material for a lithium secondary battery, including a cathode active material precursor material prepared by the method for preparing a cathode active material precursor material; and a cathode active material for a lithium secondary battery, prepared according to the method for preparing a cathode active material for a lithium secondary battery.

The present disclosure provides: a method for preparing a cathode active material precursor material by using a high-nickel-content waste lithium secondary battery; a method for preparing a cathode active material for a lithium secondary battery, including a cathode active material precursor material prepared by the method for preparing a cathode active material precursor material; and a cathode active material for a lithium secondary battery, prepared according to the method for preparing a cathode active material for a lithium secondary battery.

A method of separating and recovering a cobalt salt and a nickel salt includes a separation step of separating, by using a nanofiltration membrane, a cobalt salt and a nickel salt from a rare metal-containing aqueous solution containing at least both the cobalt salt and the nickel salt as rare metals, in which the nanofiltration membrane has a glucose permeability of 3 times or more a sucrose permeability, the sucrose permeability of 10% or less, and an isopropyl alcohol permeability of 50% or more when a 1,000 mg/L glucose aqueous solution, a 1,000 mg/L sucrose aqueous solution, and a 1,000 mg/L isopropyl alcohol aqueous solution, each having a pH of 6.5 and a temperature of 25° C., individually permeate through the nanofiltration membrane at an operating pressure of 0.5 MPa.