Use of ammonia and ammonium carbonate mixture to leaching Sarcheshmeh copper complex chalcopyrite concentrate at ambient pressure and moderate temperature

Chalcopyrite dissolution rate in atmospheric pressure in sulphate media is slower than the leaching of copper oxides and secondary sulfides due to the formation of passive layer on the particles. So the use of sulphate media in industrial scale is faced with serious problems. Due to the high recovery in chalcopyrite leaching with Ammonia and ammonium salts in atmospheric pressure، this media are considered. In this study experiments performed to investigate the parameters affecting the leaching of Sarcheshmeh chalcopyrite copper concentrate with 53. 029% chalcopyrite and 25% Cu at atmospheric pressure with ammonia and ammonium carbonate. The findings of this research showed that parameters of the concentration of ammonia، ammonium carbonate، solid to liquid ratio، stirring rate، oxygen flow rate and leaching time are the most important factors in the leaching of chalcopyrite. Under optimal conditions، 5 mol of ammonia، 0. 3 M ammonium bicarbonate، liquid to solid ratio of 20/1، stirring speed 1000 rpm، 60 ° C، oxygen flow rate of 1 liter per minute and 240 minutes of leaching time، the copper recovery was obtained more than 71%.