In this study, the batch-type experiment was used to investigate the depassivation of passivated zero-valent iron (ZVI) by electrical induced reduction (3, 6, 12 V; EIR). With 12 V electricity added, the first order degradation rate k of TCE was 4 times more than the k of the passivated ZVI, EIR is helpful to the TCE removal in ZVI PRB and this accelerate effect is roughly proportional to the electricity level. After EIR added, the k of the restored ZVI was still 3 times more than the k of the passivated ZVI. The most composition of the passivated ZVI surface is Fe3O4, but a lot of α- / β-FeOOH was generated after electricity added. This means that the dissolution and reduction of Fe3O4 during the EIR process.% 本文通过批-柱实验研究低压直流电流对已被NO3-钝化零价铁渗透中零价铁(ZVI)的催化活化,研究发现：加载12 V 低压直流电流后,阴极附近 TCE 的去除速率常数比钝化后 ZVI 的去除效率高出约4倍,低压直流电流可以催化 ZVI 去除 TCE,去除效果的增加和电压成正相关关系；同时,低压直流电流阴极可以活化已经钝化的 ZVI,活化后不加载电流时 ZVI 对 TCE 的去除效率仍是钝化后 ZVI 的去除效率的约3倍。经过 NO3-钝化后 ZVI 表面的氧化膜组成以 Fe3O4为主；但在加载低压直流电流后,ZVI 表面同时会有α-/β-FeOOH 生成,说明低压直流电可能会使 Fe3O4溶解还原。
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