METHOD OF GOLD EXTRACTION FROM CYANIDE SOLUTION Russian patent published in 1995 - IPC

FIELD: gold extraction. SUBSTANCE: before electrolysis concentrated alkaline solution (hydroxide content is 1.5 g-equiv. /l) is treated with hydrochloric acid up to the residual hydroxide concentration 0.2-0.5 g-equiv. /l, and electrolysis for gold extraction is carried out at cathode (0.005-0.01) A/cm² and volume current density (0.4-0.8) A/l at the ratio of cathode and anode surface 10-20 for time determined by formula: t KC where t electrolysis time, h; C - gold concentration (as metal) in alkaline cyanide salt, g/l; K coefficient (0.7-1.0) l x h/g. Proposed method ensures to reduce gold and to decompose cyanides. EFFECT: improved method of gold extraction.