纳滤处理模拟电镀废水

分别以硫酸铜、氯化铜、硝酸铜溶液为模拟电镀废水进行了纳滤实验,所采用纳滤膜为Osmonics的DK、DL膜和日东电工的NTR-7450膜.实验表明,三种膜通量大小顺序为DL>DK>NTR-7450,随原料液浓度的增大膜通量降低,而膜对铜离子的截留率有升高的趋势;纳滤膜对各盐的截留率大小排序为硫酸盐>氯盐>硝酸盐.实验还考察了添加其它离子对纳滤膜通量和截留率的影响.结果表明,加入CaCl2后,对DL膜性能影响不显著;加入Na2SO4后,DL膜的通量变化不明显,截留率略有升高;加入EDTA能明显提高DL膜通量和对铜离子的截留率.

Treatment of simulated electroplating wastewater by nanofiltration

The nanofiltration of simulated copper electroplating wastwater was conducted using CuSO4,CuCl2,Cu(NO3)2 solutions as raw feed.Three nanofiltration membranes,DL,DK and NTR-7450,which have different hydraulic permeabilities,were tested.The permeate flux was in the order: DL>DK>NTR-7450.The experimental results show that the rejection of Cu2 in different salt systems was in the following sequence: CuSO4>CuCl2>Cu(NO3)2.In single-salt systems,as the feed concentration increased the rejection of Cu2 increased,whereas the flux decreased.With the aim of studying the influence of possible ions on the membrane performance,nanofiltration of Cu(NO3)2 solutions in the presence of various salts(CaCl2,Na2SO4,EDTA) were carried out.The results show that the rejection of Cu2 and the permeate flux are not affected by the presence of CaCl2.When adding Na2SO4,the rejecton of Cu2 increased slightly and the flux did not changed obviously.The addition of EDTA led to an obviously increase in the rejection of Cu2 and the permeate flux.