Functionalized Fe/Cu bimetallic nanoparticles were prepared in this work for remediation of recalcitrant low-halogenated alkanes, for which the reducing capacity and process-enhancement control were investigated dealing with dichloromethane (DCM) as representative contaminant. Results show that vitamin B12 significantly promoted the performance of Fe/Cu bimetal, since rate constant of DCM-reduction for Fe/Cu-B12system (0.444h-1) exhibited much higher than that of Fe/Cu system (0.018h-1) or Fe-B12 system (0.03h-1), implying the synergistic effect of Cu and B12 on electron-donating ability of zero-valent iron. Experiments were further conducted for process control, and results showed that 5% surface Cu-coverage and pH 9.5benefits better the catalytic reduction of DCM. Possible mechanism on catalytic performance of Fe/Cu-B12 system was discussed referring to analysis on intermediate product as well as reduction kinetics. We speculated that the intermediate was prepared by dechlorination of target organic with B12as an active electron acceptor on surface of Cu0, and then quickly decomposed to B12 and hydrogenated halide, the catalytic process was completed under synergistic effects of Fe (electron donor), Cu and B12.
林英杰, 张硕, 孙力平, 邢悦. VB12协同Fe/Cu双金属去除二氯甲烷过程调控与机理[J]. 中国环境科学, 2016, 36(9): 2650-2657.
LIN Ying-jie, ZHANG Shuo, SUN Li-ping, XING Yue. Synergistic effect of vitamin B12 and Fe/Cu bimetal on reduction of dichloromethane: Mechanism study and process control. CHINA ENVIRONMENTAL SCIENCECE, 2016, 36(9): 2650-2657.
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