使用聚乙烯亚胺(PEI)辅助超滤法处理放射性废水中的铈(Ce)。着重研究了pH，聚合物/金属离子质量比(P/M)，离子浓度以及操作压力、运行时间对铈离子(Ce3+)截留率和膜渗透通量的影响。研究结果显示：使用聚合物PEI辅助超滤时，最佳实验条件为pH=5，P/M=15；在最适pH和P/M比值下，三种截留分子量超滤膜对Ce3+截留率分别为88.23%（5kDa）、87.01%（10kDa）和89.78%（30kDa）；当溶液中存在Na+和Ca2+时，膜对Ce3+的截留率将会降低。膜通量随着操作压力的增加呈线性增加；三种膜通量均随着运行时间的增加有减小的趋势，且下降率顺序为30kDa ＞10kDa＞ 5kDa。

Polyethyleneimine(PEI) was used to assist ultrafiltration to remove cerium from radioactive wastewater. The effects of pH, mass ratio of polymer to metal (P/M), ionic concentration, transmembrane pressure and processing time on retention of cerium and membrane permeate fluxeswere investigated. The results showthat when using PEI assist ultrafiltration,the optimum pH value and P/M value are 5 and 15, respectively; at the optimum conditions, the retentions of three different molecular weight cut-off (MWCO)membranesare 88.23% (5kDa), 87.01% (10kDa) and 89.78% (30kDa), respectively; in addition, the retention of cerium will decrease when Na+ and Ca2+ are exist in solution.The membranepermeate flux is linear increase with the increase of transmembrane pressure;Three kinds of membrane permeate flux have a tendency to decrease with the increase of operation time,and the rank of three membranespermeate flux decrease rate is: 30kDa ＞10kDa＞ 5kDa.

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