(中南大学 冶金与环境学院，长沙 410083)
摘 要: 针对贵州地区复杂镍钼矿难以清洁高效利用的问题，提出了碱性焙烧-净化-冷冻结晶-离子交换回收钼及副产物Na2SO4的清洁冶金工艺。采用单因素实验法，考察了碱性焙烧-浸出过程中Na2CO3用量、焙烧温度、焙烧时间、浸出温度和浸出时间等因素对钼浸出率和浸出液成分的影响，研究了冷冻结晶过程溶液中钼、硫含量对Na2SO4结晶率及产品纯度的影响。结果表明：在Na2CO3用量为理论用量的1.2倍、焙烧温度800 ℃、焙烧时间1 h、浸出温度95 ℃、浸出时间1 h的优化条件下，钼的总浸出率为94.68%。经四次循环后，浸出液中钼浓度约为40 g/L、硫浓度约为90 g/L。对循环浸出液冷冻结晶，可得到结晶率为89.61%的Na2SO4。结晶母液经离子交换得到的高峰解析液中钼浓度可达115 g/L以上。
关键字: 镍钼矿；清洁冶金；冷冻结晶；Na2SO4回收；钼回收
（School of Metallurgy and Environmental, Central South University, Changsha 410083, China）
Abstract:The Ni-Mo ore is a kind of refractory ore, which has been neglected for several decades, due to the absence of an efficient treatment process. In this paper, a metallurgy process including alkaline roasting, purification, freezing crystallization, and ion exchange for extraction of molybdenum and Na2SO4 from Ni-Mo ore has been proposed. The effects of Na2CO3 dosage, roasting temperature, roasting duration, leaching temperature and leaching duration on the leaching efficiency of molybdenum and the composition of the leachate were investigated by single-factor experiment. In addition, the effects of the concentration of molybdenum and sulfur in the leachate on the crystallization efficiency and purity of Na2SO4 were studied. The result shows the leaching efficiency of molybdenum is 94.68% with the optimal conditions in roasting-leaching process of the dosage of Na2CO3 is 1.2 times of the theoretical amount, the roasting temperature of 800 ℃, the roasting duration of 1 h, and the leaching temperature of 95 ℃. The purity of Na2SO4 produced by freezing crystallization process is 97.45% with the optimum condition of the concentration of molybdenum about 40 g/L and sulfur about 90 g/L. The concentration of molybdenum in stripping aqueous is 115 g/L, which is obtained by ion exchange.
Key words: Ni-Mo ore; clean metallurgy; freezing crystallization; Na2SO4 recovery; molybdenum recovery
