Development of an Enhanced Method for Copper Extraction from Sulfuric Acid Solutions

The paper presents a method for the extraction of copper from sulfuric acid solutions, which reduces the consumption of sulfuric acid, increases the extraction of copper and the quality of cathode copper, and reduces the undesirable formation of the third-phase crud. The main results of copper extraction, including 2-3 stepwise extraction of copper, are presented. The extraction is carried out by mixing sulfuric acid solutions with a solution of a chelating, selective extractant of the aldoxime group (10 vol.%) and separating the mixture by settling to obtain a copper-containing extract and extraction raffinate, with the suppression of the third phase-crud due to the dissolution of polymerized silicon bonds in the cruds with a monomeric polymer (H2C═CHC6H4SO3Na)n poly(4-sodium styrene sulfonate). This is achieved by adding 5 cm³ of the polymer, influenced by the surfactant complex of sodium alkyl sulfonate, with an O/A ratio of 1:2 and a temperature of 20±5°C. Subsequent re-extraction of copper from the extract is carried out by mixing the extract with a sulfuric acid solution and separating the mixture by settling to obtain a copper-containing re-extraction and an extractant solution. The re-extract is purified from impurities, and copper is extracted electrically from the purified re-extract to obtain cathode copper and waste electrolyte. A method for calculating the technical and economic choice of an extraction apparatus has also been developed.