Effects of roasting pretreatment on zinc leaching from complicated zinc ores

Green Processing and Synthesis

article

Weiheng Chen¹  Libo Zhang¹  Jinhui Peng¹  Shaohua Yin¹  Aiyuan Ma¹  Kun Yang¹  Shiwei Li¹  Feng Xie¹ 

[1] State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology;Yunnan Provincial Key Laboratory of Intensification Metallurgy;National Local Joint Laboratory of Engineering Application of Microwave Energy and Equipment Technology;Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology

关键词: ammonia leaching;    complicated zinc ores;    mineral phase transformation;    roasting;   

DOI  :  10.1515/gps-2015-0046

来源: De Gruyter

【 摘 要 】

Roasting pretreatment and ammonia leaching were performed to extract zinc from complicated zinc ores. The residue of the unroasted ore showed that the zinc containing phase ZnCO 3 cannot be effectively leached in the ammonia leaching system. Mineral phase transformation of ZnCO 3 takes place at a roasting temperature of 673 K, and this is the reason for the improvement of zinc leaching recovery. Additionally, the parameters that can influence the leaching rate of zinc such as the calcined temperature, the total ammonia concentration, the ratio of liquid to solid, the stirring speed and the leaching time were also investigated. Zinc leaching recovery from the complicated zinc ores could reach 84.7% under the following optimized experiment conditions: roasting temperature of 673 K, leaching temperature of 298 K, stirring speed of 500 rpm, total ammonia concentration of 6 mol/l, liquid to solid ratio of 11:1 and leaching time of 60 min. Compared to the zinc leaching recovery from unroasted ore (49.7%, ammonia concentration 6 mol/l), roasting pretreatment and optimization of process parameters can increase the zinc leaching recovery by 70.4%.

【 授权许可】

CC BY