A process and system are disclosed for producing a lithium product from a solution comprising lithium nitrate. The solution comprising lithium nitrate can be obtained by reacting a lithium-containing metal silicate with nitric acid. The process and system comprise subjecting the solution comprising lithium nitrate to a first thermal treatment procedure (in one or more heated vessels) in which water and nitric acid (when present) are removed, and whereby a resultant lithium nitrate-rich crystal slurry is heated to produce a molten liquid. The process and system also comprise passing the molten liquid to a second thermal treatment procedure (in a further-heated vessel) in which the molten liquid is heated to substantially decompose lithium nitrate to lithium oxide.

A process and system are disclosed for producing a lithium product from a solution comprising lithium nitrate. The solution comprising lithium nitrate can be obtained by reacting a lithium-containing metal silicate with nitric acid. The process and system comprise subjecting the solution comprising lithium nitrate to a first thermal treatment procedure (in one or more heated vessels) in which water and nitric acid (when present) are removed, and whereby a resultant lithium nitrate-rich crystal slurry is heated to produce a molten liquid. The process and system also comprise passing the molten liquid to a second thermal treatment procedure (in a further-heated vessel) in which the molten liquid is heated to substantially decompose lithium nitrate to lithium oxide.

A process and system are disclosed for producing a lithium product from a solution comprising lithium nitrate. The solution comprising lithium nitrate can be obtained by reacting a lithium-containing metal silicate with nitric acid. The process and system comprise subjecting the solution comprising lithium nitrate to a first thermal treatment procedure (in one or more heated vessels) in which water and nitric acid (when present) are removed, and whereby a resultant lithium nitrate-rich crystal slurry is heated to produce a molten liquid. The process and system also comprise passing the molten liquid to a second thermal treatment procedure (in a further-heated vessel) in which the molten liquid is heated to substantially decompose lithium nitrate to lithium oxide.

A method for improving the particle size and morphology of a neutralizing agent used in the laterite nickel ore hydrometallurgy, in a process flow for producing nickel-cobalt-manganese hydroxide by the laterite nickel ore hydrometallurgy, a nickel-cobalt-manganese-containing feed liquid is subjected to one-stage iron-aluminum removal treatment and two-stage iron-aluminum removal treatment by using a neutralizing agent successively, wherein the 200 mesh sieving rate by mass ratio of the neutralizing agent is 85%-90%, and the spherical coefficient of solid particles of the neutralizing agent is not less than 0.6. In the disclosure, the particle size and morphology of the neutralizing agent are respectively improved so as to be used in the steps of one-stage iron-aluminum removal treatment and two-stage iron-aluminum removal treatment. The iron-aluminum removal rates in the steps of one-stage iron-aluminum removal treatment and two-stage iron-aluminum removal treatment can be effectively increased, and at the same time, the surface roughness of the solid particles of the neutralizing agent can be ensured to be lower, thereby reducing the rates of nickel, cobalt, and manganese ions reacting with local alkali to generate precipitations, thereby reducing the loss of nickel, cobalt, and manganese and further improving the yield of nickel-cobalt-manganese hydroxide produced by the laterite nickel ore hydrometallurgy.

A method for improving the particle size and morphology of a neutralizing agent used in the laterite nickel ore hydrometallurgy, in a process flow for producing nickel-cobalt-manganese hydroxide by the laterite nickel ore hydrometallurgy, a nickel-cobalt-manganese-containing feed liquid is subjected to one-stage iron-aluminum removal treatment and two-stage iron-aluminum removal treatment by using a neutralizing agent successively, wherein the 200 mesh sieving rate by mass ratio of the neutralizing agent is 85%-90%, and the spherical coefficient of solid particles of the neutralizing agent is not less than 0.6. In the disclosure, the particle size and morphology of the neutralizing agent are respectively improved so as to be used in the steps of one-stage iron-aluminum removal treatment and two-stage iron-aluminum removal treatment. The iron-aluminum removal rates in the steps of one-stage iron-aluminum removal treatment and two-stage iron-aluminum removal treatment can be effectively increased, and at the same time, the surface roughness of the solid particles of the neutralizing agent can be ensured to be lower, thereby reducing the rates of nickel, cobalt, and manganese ions reacting with local alkali to generate precipitations, thereby reducing the loss of nickel, cobalt, and manganese and further improving the yield of nickel-cobalt-manganese hydroxide produced by the laterite nickel ore hydrometallurgy.