酒石酸钾钠（PST）对纳滤处理重金属废水的强化效果

以酒石酸钾钠（PsT）为络合剂，分别选取cd、zn、As和Ph4种金属废水，探索络合纳滤工艺对金属离子去除率和膜通量的强化效果，测定纳滤膜表面接触角以表征膜通量变化规律，并研究了压力、金属浓度和溶液pH参数对络合纳滤过程的影响。结果表明，PsT对4种金属去除的强化效果存在相似规律，分别有一个最佳PsT添加浓度。随PsT浓度的增加，金属离子去除率先增大后减小，而膜通量一直增大。研究发现，纳滤膜表面接触角与膜通量呈稳定的反比例关系，与金属离子种类和PsT添加量无关。随着操作压力的增大，膜通量线性增加，去除率基本不变；金属离子浓度的增加对膜通量影响不大，金属去除率略有上升；pH在4～5之间变化时，As去除中膜通量和去除率均有所升高，而cd、zn和Ph3种溶液处理效果基本不受pH影响。

Enhancing effect of potassium sodium tartrate （PST） in nanofiltration process for treatment of heavy metal wastewater

Potassium sodium tartrate （PST） was chosen as the complexing agent to study the enhanced effects of nanofiltration for the removal of cadmium, zinc, arsenic and lead from wastewater. Contact angles of membrane surface were measured to describe the change of flux. The effects of applied pressure, feed concentra- tion and pH on metal ion separation were examined. The results showed the t：our metals had quite similar experi- mental results,and that the rejection increased and then decreased with increasing PST concentration. Unexpect- edly, the permeate flux was found to increase over the entire range, which was quite different from what was repor- ted in previous complexation studies.β was inversely proportional to permeate flux no matter what the metal ions or PST addition were. Increasing the operating pressure did not improve metal rejection,but the flux increased lin- early. The rejection coefficient increased slightly with increasing feed concentrations, while the flux remained al- most constant in the range. The flux and the rejection of As both increased when pH increased from 4 to 5, but the removal results of Cd,Zn and Pb weren＇ t affected by pH.