A process for generating a metal sulfate that involves crystallizing a metal sulfate from an aqueous solution to form a crystallized metal sulfate in a mother liquor with uncrystallized metal sulfate remaining in the mother liquor; separating the crystallized metal sulfate from the mother liquor; basifying a portion of the mother liquor to convert the uncrystallized metal sulfate to a basic metal salt; and using the basic metal salt upstream of crystallizing the metal sulfate. So crystallized, the generated metal sulfate may be battery-grade or electroplating-grade.

A process for generating a metal sulfate that involves crystallizing a metal sulfate from an aqueous solution to form a crystallized metal sulfate in a mother liquor with uncrystallized metal sulfate remaining in the mother liquor; separating the crystallized metal sulfate from the mother liquor; basifying a portion of the mother liquor to convert the uncrystallized metal sulfate to a basic metal salt; and using the basic metal salt upstream of crystallizing the metal sulfate. So crystallized, the generated metal sulfate may be battery-grade or electroplating-grade.

Provided is a method for efficiently recovering metals from lithium ion battery waste while reducing the use of sodium hydroxide as a pH adjuster. A method for recovering metals from lithium ion battery waste includes wet processing of leaching metals containing lithium from lithium ion battery waste with an acid, and extracting the metals from the metal-containing solution in which the metals are dissolved, in which the lithium extracted in the wet processing is used as a pH adjuster used in the wet processing.

Provided is a method for efficiently recovering metals from lithium ion battery waste while reducing the use of sodium hydroxide as a pH adjuster. A method for recovering metals from lithium ion battery waste includes wet processing of leaching metals containing lithium from lithium ion battery waste with an acid, and extracting the metals from the metal-containing solution in which the metals are dissolved, in which the lithium extracted in the wet processing is used as a pH adjuster used in the wet processing.

In one aspect, a preparation method of iron phosphate includes: mixing pyrite cinder and an sulfite evenly in water to obtain a first mixed system; adding phosphoric acid and a buffer to the first mixed system to perform a leaching reaction; performing a first solid-liquid separation on a slurry obtained from the leaching reaction to obtain a first filtrate and a first residue; introducing air into the first filtrate and then performing a first stirring reaction on the first filtrate; performing a second solid-liquid separation on a slurry obtained from the first stirring reaction to obtain a second filtrate and a second residue; and calcining the second residue to obtain iron phosphate.

In one aspect, a preparation method of iron phosphate includes: mixing pyrite cinder and an sulfite evenly in water to obtain a first mixed system; adding phosphoric acid and a buffer to the first mixed system to perform a leaching reaction; performing a first solid-liquid separation on a slurry obtained from the leaching reaction to obtain a first filtrate and a first residue; introducing air into the first filtrate and then performing a first stirring reaction on the first filtrate; performing a second solid-liquid separation on a slurry obtained from the first stirring reaction to obtain a second filtrate and a second residue; and calcining the second residue to obtain iron phosphate.

Process to decrease silicon content of metal powder produced by hydrogen reduction from ammoniacal ammonium sulphate solutions containing metal ammine complexes, wherein metal (Me) is Ni, Co, or Cu. The process controls the precipitation of metal hydroxide, which is found to be an effective scavenger for silicon. Silicon is preferentially removed from metal diammine sulphate-containing solutions by precipitating with a small amount of a metal hydroxide, and then separating the silicon-bearing metal hydroxide precipitate from the solution. This solution, from which the silicon impurity has been removed with the metal hydroxide precipitate, can then be reduced in one or more densification cycles with a reducing gas to produce an elemental metal powder having a decreased silicon content. Alternatively, the solution is reduced to produce a low silicon metal powder seed material for the first of the one or more densification cycles.

Process to decrease silicon content of metal powder produced by hydrogen reduction from ammoniacal ammonium sulphate solutions containing metal ammine complexes, wherein metal (Me) is Ni, Co, or Cu. The process controls the precipitation of metal hydroxide, which is found to be an effective scavenger for silicon. Silicon is preferentially removed from metal diammine sulphate-containing solutions by precipitating with a small amount of a metal hydroxide, and then separating the silicon-bearing metal hydroxide precipitate from the solution. This solution, from which the silicon impurity has been removed with the metal hydroxide precipitate, can then be reduced in one or more densification cycles with a reducing gas to produce an elemental metal powder having a decreased silicon content. Alternatively, the solution is reduced to produce a low silicon metal powder seed material for the first of the one or more densification cycles.

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.