Copper hydrometallurgy

Claim 1

SUBJECTING A COPPER BEARING MATERIAL TO A LEACH WITH A HOT FERRIC CHLORIDE CONTAINING LIXIVIANT,

Claim 22

A method for recovering copper and sulfur values from a copper and sulfide bearing material which comprises the steps of: a) subjecting said copper and sulfide bearing material to a leach with a lixiviant containing 50 to 200 grams per litre of iron as ferric chloride at a temperature within the range of 80* C up to the boiling point of the reaction mixture, b) separating the reaction mixture thereby formed into a solids residue and a leach solution containing cuprous and cupric and ferrous chlorides, c) treating said solids residue by froth flotation thereby separating elemental sulfur and sulfides present therein from the residual tailings thus formed, d) separating said elemental sulfur from said sulfides and separately recovering the elemental sulfur and said sulfides, e) reducing the cupric ions in the leach solution separated in step b) to the cuprous state with metallic copper, f) crystallizing at least a portion of the cuprous chloride from said leach solution after reduction and separating the cuprous chloride crystals thereby formed, g) treating said cuprous chloride crystals with hydrogen at a temperature between 300* and 500* C to recover elemental copper and, h) treating the ferrous chloride with hydrochloric acid and oxygen to regenerate the ferric chloride containing lixiviant and to simultaneously precipitate ferric oxide.

Claim 23

A method for recovering copper and sulfur values from a copper and sulfide bearing material which comprises the steps of: a) subjecting said copper and sulfide bearing material to a leach with a lixiviant containing 50 to 200 grams per litre of iron as ferric chloride at a temperature within the range of 80* C up to the boiling point of the reaction mixture, b) separating the reaction mixture thereby formed into a solids residue and a leach solution containing cuprous and cupric and ferrous chlorides, c) treating said solids residue by froth flotation thereby separating elemental sulfur and sulfides present therein from the residual tailings thus formed, d) separating said elemental sulfur from said sulfides and separately recovering the elemental sulfur and said sulfides, e) reducing the cupric ions in the leach solution separated in step b) to the cuprous state with metallic copper, f) crystallizing at least a portion of the cuprous chloride from said leach solution after reduction and separating the cuprous chloride crystals thereby formed, g) treating said cuprous chloride crystals with hydrogen at a temperature between 300* and 500* C to recover elemental copper and, h) treating the ferrous chloride with hydrochloric acid and oxygen to regenerate the ferric chloride containing lixiviant and to simultaneously precipitate ferric oxide.

Claim 33

A method of recovering copper, iron and sulfur values from copper, iron and sulfide bearing materials which comprises the steps of: a) subjecting said copper, iron and sulfide bearing material to a leach with a lixiviant containing 50 to 200 grams per litre of iron as ferric chloride at a temperature within the range of 80* C up to the boiling point of the reaction mixture, b) separating the reaction mixture thereby formed into a solids residue and a leach solution containing cuprous and cupric and fErrous chlorides, c) treating said solids residue by froth flotation thereby separating elemental sulfur and sulfides present therein from the residual tailings thus formed, d) separating said elemental sulfur from said sulfides and separately recovering the elemental sulfur and sulfides, e) reducing the cupric ions in the leach solution separated in step b) to the cuprous state with metallic copper, f) crystallizing at least a portion of the cuprous chloride from said leach solution after reduction and separating the cuprous chloride crystals thereby formed, g) treating said cuprous chloride crystals with hydrogen at a temperature between 300* and 500* C to form elemental copper and hydrogen chloride gas, h) treating the mother liquor from crystallization step f) with metallic iron to precipitate its copper content as metallic copper, i) bleeding off a portion of the residual solution after precipitation in an amount to remove a predetermined quantity of impurities from said solution, j) separately recovering ferrous chloride, impurities and hydrogen chloride from said portion, k) reacting hydrogen chloride gas from steps g) and j), the remaining portion of the residual solution after step i) and the recovered ferrous chloride from step j) with oxygen under pressure to thereby regenerate a predetermined amount of ferric chloride containing lixiviant and to simultaneously precipitate the remaining iron content into ferric oxide, and, l) reducing said ferric oxide to metallic iron.

Claim 34

A method of recovering copper, iron and sulfur values from copper, iron and sulfide bearing materials which comprises the steps of: a) subjecting said copper, iron and sulfide bearing material to a leach with a lixiviant containing 50 to 200 grams per litre of iron as ferric chloride at a temperature within the range of 80* C up to the boiling point of the reaction mixture, b) separating the reaction mixture thereby formed into a solids residue and a leach solution containing cuprous and cupric and fErrous chlorides, c) treating said solids residue by froth flotation thereby separating elemental sulfur and sulfides present therein from the residual tailings thus formed, d) separating said elemental sulfur from said sulfides and separately recovering the elemental sulfur and sulfides, e) reducing the cupric ions in the leach solution separated in step b) to the cuprous state with metallic copper, f) crystallizing at least a portion of the cuprous chloride from said leach solution after reduction and separating the cuprous chloride crystals thereby formed, g) treating said cuprous chloride crystals with hydrogen at a temperature between 300* and 500* C to form elemental copper and hydrogen chloride gas, h) treating the mother liquor from crystallization step f) with metallic iron to precipitate its copper content as metallic copper, i) bleeding off a portion of the residual solution after precipitation in an amount to remove a predetermined quantity of impurities from said solution, j) separately recovering ferrous chloride, impurities and hydrogen chloride from said portion, k) reacting hydrogen chloride gas from steps g) and j), the remaining portion of the residual solution after step i) and the recovered ferrous chloride from step j) with oxygen under pressure to thereby regenerate a predetermined amount of ferric chloride containing lixiviant and to simultaneously precipitate the remaining iron content into ferric oxide, and, l) reducing said ferric oxide to metallic iron.