扩散渗析法从钛白废酸中回收硫酸

Recovery of Sulfuric Acid from Titanium White Waste Acid by Diffusion Dialysis

针对钛白废酸的回收,在静态扩散条件下测定了硫酸、硫酸亚铁在阴离子交换膜中的渗析系数以考察膜的分离性能。进一步考察动态扩散操作参数如流量、流量比、停留时间等对回收率及回收酸浓度的影响。研究表明,使用的阴离子交换膜具有良好的分离性能,酸盐分离系数达23.6,在水酸流量比维持在1～1.1,废酸流量维持在0.6L·h-1左右的条件下,硫酸回收率大于85%,硫酸亚铁透过率小于7%。

Using diffusion dialysis to recover the sulfuric acid from titanium white waste acid was studied. Dialysis coefficient of sulfuric acid and ferrous sulfate for the anion exchange membrane (DF120) was measured by using simulated system under the static conditions. The effect of operating parameters of dynamic state diffusion dialysis on acid recovery rate and acid concentration was investigated further. The studied parameters included flow rate of feed, ratio of water to feed and residence time. The results showed that DF120 membrane used has good separation property. Dialysis coefficient of sulfuric acid and ferrous sulfate are 4.0210-3 mh-1 and 1.7010-4mh-1 respectively, and the separation factor between acid and salt is 23.6. Under the conditions of flow rate ratio of water to waste acid 1~1.1, feed flow rate 0.6Lh-1, the acid recovery rate is more than 85%, and the salt leakage rate is less than 7%.