真空碳热还原处理氧化锌矿理论分析及实验研究

Theoretical and Experimental Studies of Vacuum Carbothemic Reduction of Zinc-Oxide Ores

通过热力学计算和理论分析表明,在真空条件下可有效降低氧化锌矿中氧化物碳热还原反应的临界温度;将蒸馏出的气体进行分段冷凝,可将Pb,As,Cd与Zn分离。实验证实,在多级冷凝真空炉内,可以降低氧化锌的还原温度,在温度1173 K,压强50 Pa条件下真空蒸馏还原1 h,氧化铅锌矿中约96.82%的Zn被还原蒸馏出来,Zn的纯度达到99.95%以上。

A novel technique was developed to significantly reduce the critical carbothemic reduction temperature of the zinc-oxide ores. In the technique, various volatile components, released under the vacuum condition, were consecutively condensed in the dedicated multi-stage condenser of the vacuum setup, and metals of Pb, As, and Cd can be effectively separated from Zn. The vacuum carbothemic reduction of zinc oxide was calculated and experimentally evaluated. The pre- liminary results show that vacuum condition lowers the critical carbothemie reduction temperature of the ore. At 1173K and a pressure of 50Pa, the vacuum reduction and distillation for one hour resulted in the extraction of 96.82% of zinc, with a purity up to 99.95 %, from the zinc oxide ore.