Study on recovery of copper and zinc from cyanide lean solution in a smelting company Qin Guanglin, Li Guangsheng, Zhu Xingfu, Gao Tengyue, Chen Yanbo, Ji Qiang, Yu Congquan, Lu Zhongbo, Zhang Juntong, Xu Chao and Cai Mingming E3S Web Conf., 271 (2021) 04004 Published online: 15 June 2021 DOI: 10.1051/e3sconf/202127104004