School of Civil Engineering, Wuhan University, No. 8, East Lake South Road, Wuhan, PR China; Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark; Department of Chemistry, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark.
Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark.
J Hazard Mater. 2018 Mar 5;345:18-26. doi: 10.1016/j.jhazmat.2017.11.011. Epub 2017 Nov 6.
A layered Fe-Fe hydroxide (green rust, GR) was intercalated with dodecanoate (known as GR) and then amended with Cu (GR(Cu)) before reaction with chloroform (CF), carbon tetrachloride (CT), trichloroethylene (TCE) or tetrachloroethylene (PCE). Reduction of CT by GR(Cu) was 37 times faster than with GR alone before the active Cu species was consumed. The Cu mediated reaction followed the dichloroelimination pathway as observed for GR alone, with carbon monoxide (82.5%) and formate (26.6%) as main degradation products. Also, CF was reduced by GR(Cu), which is not seen with GR. Neither GR(Cu) nor GR reacted with PCE or TCE. The chlorinated solvents can partition into dodecanoate interlayer but only small CS molecules (CF, CT) can transport through the dodecanoate interlayer. Copper(II) added to GR was reduced to Cu by Fe in GR, but Cu was not regenerated during the dechlorination. High resolution TEM showed that Cu was evenly distributed in the GR without formation of Cu nanoparticles on edges of GR. The active Cu sites are most likely located between the iron hydroxide layer and the hydrated negatively charged carboxylate groups in the interlayer of GR. This work shines new light on the Cu accelerated dechlorination by GR.
层状 Fe-Fe 氢氧化物（绿色锈，GR）被十二烷酸酯（称为 GR）插层，然后用 Cu（GR(Cu)）修饰，然后与氯仿（CF）、四氯化碳（CT）、三氯乙烯（TCE）或四氯乙烯（PCE）反应。在活性 Cu 物种被消耗之前，GR(Cu) 还原 CT 的速度比单独的 GR 快 37 倍。Cu 介导的反应遵循与单独的 GR 相同的二氯消除途径，主要降解产物为一氧化碳（82.5%）和甲酸盐（26.6%）。此外，GR(Cu) 还原 CF，而 GR 则不能还原 CF。GR(Cu) 和 GR 均不与 PCE 或 TCE 反应。氯化溶剂可以分配到十二烷酸酯层间，但只有小分子 CS（CF、CT）可以通过十二烷酸酯层间运输。添加到 GR 中的 Cu(II) 被 GR 中的 Fe 还原为 Cu，但在脱氯过程中 Cu 没有再生。高分辨率 TEM 表明，Cu 在 GR 中均匀分布，GR 边缘没有形成 Cu 纳米颗粒。活性 Cu 位点很可能位于 GR 的铁氢氧化物层和层间带负电荷的水合羧酸盐之间。这项工作为 GR 加速脱氯的 Cu 提供了新的认识。
