Gui Minghui, Ormsbee Lindell E, Bhattacharyya Dibakar
Department of Chemical and Materials Engineering, University of Kentucky, Lexington, KY 40506.
Department of Civil Engineering, University of Kentucky, Lexington, KY 40506.
Ind Eng Chem Res. 2013 Aug 7;52(31):10430-10440. doi: 10.1021/ie400507c.
Membranes have been widely used in water remediation (e.g. desalination and heavy metal removal) because of the ability to control membrane pore size and surface charge. The incorporation of nanomaterials into the membranes provides added benefits through increased reactivity with different functionality. In this study, we report the dechlorination of 2-chlorobiphenyl in the aqueous phase by a reactive membrane system. Fe/Pd bimetallic nanoparticles (NPs) were synthesized (in-situ) within polyacrylic acid (PAA) functionalized polyvinylidene fluoride (PVDF) membranes for degradation of polychlorinated biphenyls (PCBs). Biphenyl formed in the reduction was further oxidized into hydroxylated biphenyls and benzoic acid by an iron-catalyzed hydroxyl radical (OH•) reaction. The formation of magnetite on Fe surface was observed. This combined pathway (reductive/oxidative) could reduce the toxicity of PCBs effectively while eliminating the formation of chlorinated degradation byproducts. The successful manufacturing of full-scale functionalized membranes demonstrates the possibility of applying reactive membranes in practical water treatment.
由于能够控制膜孔径和表面电荷,膜已广泛应用于水修复(如脱盐和去除重金属)。将纳米材料掺入膜中,通过增加与不同功能的反应性带来了额外的好处。在本研究中,我们报道了一种反应性膜系统对水相中2-氯联苯的脱氯作用。在聚丙烯酸(PAA)功能化的聚偏氟乙烯(PVDF)膜中原位合成了铁/钯双金属纳米颗粒(NPs),用于降解多氯联苯(PCBs)。还原过程中形成的联苯通过铁催化的羟基自由基(OH•)反应进一步氧化为羟基化联苯和苯甲酸。观察到铁表面形成了磁铁矿。这种联合途径(还原/氧化)可以有效降低多氯联苯的毒性,同时消除氯化降解副产物的形成。全尺寸功能化膜的成功制造证明了在实际水处理中应用反应性膜的可能性。