There are provided processes comprising submitting an aqueous composition comprising lithium sulphate and/or bisulfate to an electrolysis or an electrodialysis for converting at least a portion of said sulphate into lithium hydroxide. During electrolysis or electrodialysis, the aqueous composition is at least substantially maintained at a pH having a value of about 1 to about 4; and converting said lithium hydroxide into lithium carbonate. Alternatively, lithium sulfate and/or lithium bisulfate can be submitted to a first electromembrane process that comprises a two-compartment membrane process for conversion of lithium sulfate and/or lithium bisulfate to lithium hydroxide, and obtaining a first lithium-reduced aqueous stream and a first lithium hydroxide-enriched aqueous stream; and submitting said first lithium-reduced aqueous stream to a second electromembrane process comprising a three-compartment membrane process to prepare at least a further portion of lithium hydroxide and obtaining a second lithium-reduced aqueous stream and a second lithium-hydroxide enriched aqueous stream.

Disclosed is a method for recycling a hydrogen fuel cell of a new energy vehicle, including the following steps of: (1) discharging and disassembling a hydrogen fuel cell in turn to obtain a hydrogen supply system, an air supply system, a cooling system and a galvanic pile; (2) disassembling the galvanic pile into a catalyst and carbon cloth, and ashing to obtain ash; (3) adding an auxiliary agent into the ash, mixing, introducing inert gas, heating, introducing oxidizing gas, and absorbing tail gas by using an ammonium salt solution; and (4) adding a reducing agent into the ammonium salt solution absorbing the tail gas in step (3) to react, filtering, taking and cleaning a filter residue to obtain Pt.

The present invention provides an environmentally safe method of collecting rare earth elements from mineral sources such as bastnasite deposits. The invention uses calcium hydroxide to decompose rare earth element minerals and avoids the use of sulfuric acid decomposition which produces toxic hydrofluoric acid as a byproduct. The invention's use of calcium hydroxide produces calcium fluoride as a byproduct which is non-toxic and has a number of industrial uses. The invention further provides a method of separating mixed rare earth element leachates into heavy and light rare earth element fractions using inorganic sodium salts as a precipitation agent.

The present invention provides an environmentally safe method of collecting rare earth elements from mineral sources such as bastnasite deposits. The invention uses calcium hydroxide to decompose rare earth element minerals and avoids the use of sulfuric acid decomposition which produces toxic hydrofluoric acid as a byproduct. The invention's use of calcium hydroxide produces calcium fluoride as a byproduct which is non-toxic and has a number of industrial uses. The invention further provides a method of separating mixed rare earth element leachates into heavy and light rare earth element fractions using inorganic sodium salts as a precipitation agent.

A method and system for converting copper cyanide to copper oxide is provided. The method includes contacting a copper cyanide solution with an acidic solution in a precipitation tank under reaction conditions sufficient to produce a copper cyanide slurry, removing the copper cyanide slurry from the precipitation tank, separating solid copper cyanide from the copper cyanide slurry in a first separation device, removing the solid copper cyanide from the first separation device, contacting the solid copper cyanide with a sodium hydroxide solution in a production tank under reaction conditions sufficient to produce a copper oxide slurry, removing the copper oxide slurry from the production tank, separating solid copper oxide from the copper oxide slurry in a second separation device, and removing from the second separation device any residual sodium hydroxide not reacted during the process of contacting the solid copper cyanide with the sodium hydroxide solution in the production tank.

A method for recycling a battery including the following steps: a) dissolution of a battery waste, for example an electrode, including lithium and a metal selected from cobalt and manganese, such that a solution to be treated containing lithium ions and metal ions is formed, b) addition of a peroxymonosulfate salt to the solution to be treated, the solution to be treated being regulated at a pH ranging from 1 to 4 when the metal is cobalt or at a pH ranging from 0.1 to 2.5 when the metal is manganese, such that the metal ions are selectively precipitated in the form of metal oxyhydroxide, c) separation of the lithium ions from the solution to be treated. Advantageously, the solution further comprises nickel ions.

An apparatus, method and system are provided to recover constituent components from single use batteries. In particular, the apparatus, method and system may be used to recover zinc and manganese in the form of sulfates from depleted commercial which in turn may be subsequently used for other applications, such as micronutrients and fertilizers.

Provided is a method for separating lithium from a lithium solution containing lithium by 200 mg/L or more and fluorine by 20 mg/L or more, the method including: a first removal step of adding a first component, which solidifies the fluorine contained in the lithium solution, to the lithium solution and removing the fluorine solidified to obtain a F-removed liquid; and a second removal step of adding a second component, which solidifies the first component remaining in the F-removed liquid, to the F-removed liquid and removing the first component solidified to obtain a first component-removed liquid.

Provided is a method for separating lithium from a lithium solution containing lithium by 200 mg/L or more and fluorine by 20 mg/L or more, the method including: a first removal step of adding a first component, which solidifies the fluorine contained in the lithium solution, to the lithium solution and removing the fluorine solidified to obtain a F-removed liquid; and a second removal step of adding a second component, which solidifies the first component remaining in the F-removed liquid, to the F-removed liquid and removing the first component solidified to obtain a first component-removed liquid.

A vanadium recovery process (10), the process comprising: (i) passing an ore or concentrate (12) containing vanadium, titanium and iron to a reduction step (18) forming a reduced ore or concentrate; (ii) passing the reduced ore or concentrate to a ferric leach step (22) to produce a ferric leachate (26) containing iron and a ferric leach residue (30) containing vanadium; (iii) passing the ferric leachate (26) to a ferric oxidation step (28) producing an iron product (68); (iv) passing the ferric leach residue (30) to an acid leach step (32) producing an acid leachate (44) containing vanadium and an acid leach residue (36) containing titanium; (v) Passing the acid leachate (44) to a vanadium recovery step (46, 48) from which a vanadium product is produced; and (vi) Passing the acid leach residue (36) to a titanium pigment production process (42) whereby a titanium dioxide pigment is produced.