Enhanced degradation of trichloroethylene in nano-scale zero-valent iron Fenton system with Cu(II)

► Addition of Cu(II) can enhance the reactivity of nZVI Fenton system. ► Excessive addition of nZVI to Cu/nZVI Fenton system did not improve TCE degradation. ► Increasing Cu(II) caused a linear increase of Fe(II) release from nZVI surface. ► Cu/nZVI Fenton system can be applied to TCE-contaminated sites at circum-neutral pHs.