Foster James C, DeVol Timothy A, Husson Scott M
Department of Chemical and Biomolecular Engineering, Clemson University, 127 Earle Hall, Clemson, SC 29634, USA.
Nuclear Environmental Engineering Sciences, Radioactive Waste Management Center, Clemson University, Clemson, SC 29625, USA.
Membranes (Basel). 2021 Dec 21;12(1):3. doi: 10.3390/membranes12010003.
This contribution describes the fabrication of plutonium-adsorptive membranes by non-solvent induced phase separation. The dope solution comprised poly(vinylidene fluoride) (PVDF) and a Pu-extractive copolymer additive of PVDF--poly(ethylene glycol methacrylate phosphate) (EGMP) in dimethylformamide (DMF). The effects of casting conditions on membrane permeability were determined for PVDF membranes prepared with 10 wt% PVDF--EGMP. Direct-flow filtration and alpha spectrometry showed that membranes containing the graft copolymer could recover Pu up to 59.9 ± 3.0% from deionized water and 19.3 ± 3.5% from synthetic seawater after filtering 10 mL of 0.5 Bq/mL Pu. SEM-EDS analysis indicated that the graft copolymer was distributed evenly throughout the entire depth of the copolymer membranes, likely attributing to the tailing observed in the alpha spectra for Pu. Despite the reduction in resolution, the membranes exhibited high Pu uptake at the conditions tested, and new membrane designs that promote copolymer surface migration are expected to improve alpha spectrometry peak energy resolutions. Findings from this study also can be used to guide the development of extractive membranes for chromatographic separation of actinides from contaminated groundwater sources.
本文介绍了通过非溶剂诱导相分离制备钚吸附膜的方法。铸膜液由聚偏氟乙烯（PVDF）和PVDF-聚（甲基丙烯酸乙二醇酯磷酸酯）（EGMP）的钚萃取共聚物添加剂在二甲基甲酰胺（DMF）中组成。测定了用10 wt% PVDF-EGMP制备的PVDF膜的流延条件对膜渗透性的影响。直流过滤和α能谱分析表明，含有接枝共聚物的膜在过滤10 mL 0.5 Bq/mL钚后，从去离子水中可回收钚高达59.9±3.0%，从合成海水中可回收19.3±3.5%。扫描电子显微镜-能谱分析（SEM-EDS）表明，接枝共聚物均匀分布在共聚物膜的整个深度，这可能是钚的α能谱中出现拖尾现象的原因。尽管分辨率有所降低，但在测试条件下，这些膜表现出较高的钚吸附量，预计促进共聚物表面迁移的新膜设计将提高α能谱峰能量分辨率。本研究结果还可用于指导从受污染地下水源中色谱分离锕系元素的萃取膜的开发。
