纳滤法回收湿法冶锌污酸研究

Research on Recovery of Zinc Hydrometallurgical Waste Acid by Nanofilteration

通过使用纳滤技术在一定条件下对硫酸锌、氯化锌和氟化钠混合溶液模拟的被氧化锌中和后的湿法冶锌工业污酸废液进行分离,通过调节不同的压力和流速找到了纳滤膜对中和后污酸分离过程中通量和截留率的影响规律,找到最优条件是压力为32 bar,流速为2 L/min。此条件下纳滤装置通量为89.09 L·h^(-1)/m^2,二价离子截率约为94%,氯离子、氟离子和钠离子截留率分别为35.61%、48.10%和24.31%,将大部分氯离子和氟离子分离,得到硫酸锌溶液。硫酸锌溶液经过净化步骤可以再进行电沉积得到金属锌。

Zinc sulphate, zinc chloride and sodium fluoride mixed solution as simulated wet zinc metallurgical industrial waste acid liquid after zinc oxide neutralization was separated by the nanofiltration technology under a certain condition, the influence of pressure and flow rate on the flux and the retention rate of the nanofiltration membrane during the waste acid separation process after the neutralization was investigated. The optimal conditions were determined as follows： the pressure 32 bar and the flow rate 2 L/min.Under above conditions, the flux of the nanofiltration device reached 89.09 L·h（-1）/m2, the divalent ion interception rate was about 94%,the rejection rates of chloride ion, fluoride ion, and sodium ion were 35.61%, 48.10%, and 24.31%, respectively. Most of the chloride ions and fluoride ions were separated to obtain zinc sulfate solution. The zinc sulphate solution can be further electrodeposited to obtain metallic zinc after the purification.