微波强化与常规盐酸浸出赤泥回收Ga的工艺研究

Study on the Process of Gallium Recovery from Red Mud by Microwave-assisted or Traditional Hydrochloric Acid Leaching

采用盐酸为浸出剂,考察了在常规和微波强化作用下盐酸浸出赤泥回收Ga过程中浸出温度、浸出时间、盐酸体积与赤泥质量比和盐酸浓度对Ga浸出率的影响。通过正交实验分别确定了Ga浸出率影响因素的主次顺序以及优化的浸出条件。结果表明,常规盐酸浸出过程中Ga浸出率影响因素的主次顺序及最佳浸出条件为:浸出温度100℃、浸出时间4h、盐酸浓度8mol/L以及盐酸体积与赤泥质量比7mL∶1g;而采用微波强化盐酸浸出时,Ga浸出率影响因素的主次顺序及最佳浸出条件为:浸出温度80℃、浸出时间25min、盐酸体积与赤泥质量比7mL∶1g以及盐酸浓度7mol/L。相比常规盐酸浸出,微波强化盐酸浸出的Ga浸出率更高,浸出温度更低,浸出时间明显缩短,盐酸浓度也更低。

Using hydrochloric acid as leaching agent,the influences were investigated of leaching temperature,leaching time,ratio of hydrochloric acid volume to red mud mass,and HCl concentration on gallium leaching rate during gallium recovery from red mud by traditional or microwave-assisted hydrochloric acid leaching.The primary and secondary sequence of the factors affecting gallium leaching rate was determined through the orthogonal tests as well as the optimum leaching conditions.The results show that the optimum leaching conditions of traditional hydrochloric acid leaching according to the primary and secondary sequence are as follows：leaching temperature of 100℃,time of 4h,HCl concentration of 8mol/L,and the ratio of hydrochloric acid volume to red mud mass of 7mL∶1g.And those of microwave-assisted hydrochloric acid leaching are as follows：leaching temperature of 80 ℃,leaching time of 25 min,the ratio of hydrochloric acid volume to red mud mass of 7mL∶1g,and HCl concentration of 7mol/L.Compared with traditional hydrochloric acid leaching process,microwave-assisted hydrochloric acid leaching process has higher gallium leaching rate,lower leaching temperature,shorter leaching time and lower hydrochloric acid concentration.