Extraction of cobalt from laterite ores by citric acid in presence of ammonium bifluoride

来源期刊：中国有色金属学报(英文版)2010年第8期

论文作者：李光辉 饶明军 李骞 彭志伟 姜涛

文章页码：1517 - 1520

Key words：laterite; cobalt; citric acid; ammonium bifluoride

Abstract: Citric acid was used to selectively extract cobalt from limonite-type laterite ores in the presence of ammonium bifluoride. The results show that ammonium bifluoride enhances the leaching of cobalt by citric acid, and 84.5% cobalt is extracted from a laterite ore containing 0.13% Co when leached at ambient temperature for 2 h with 30 g/L citric acid and 10 g/L ammonium bifluoride. Pyrolusite is reduced by citric acid during leaching, cobalt intergrown with which is liberated and subsequently chelated by the citric acid. The extraction of cobalt is enhanced in the presence of ammonium bifluoride because the matrix of silicate minerals is destroyed by ammonium bifluoride and the adsorbed cobalt is subsequently liberated.