Preparation of Fe/Cu bimetals by ball milling iron powder and copper sulfate for trichloroethylene degradation: Combined effect of FeSx and Fe/Cu alloy.

The addition of a secondary metal (such as Cu, Co, Ni and Pd) to form iron-based bimetallic particles could enhance the reactivity of zero valent iron (ZVI). This study proposed a new synthesis method for preparing Cu-Fe bimetals (Cu-Febm (CuSO4)) by ball milling mZVI and CuSO4. During ball-milling process, 40% of Cu2+ can be reduced to Cu0, which formed galvanic couple with Fe0 in a way of Fe/Cu alloy structure. Part Cu2+ was only reduced to Cu+ (corresponding to Cu2O), while 29% of SO42- was reduced to Sx2- (corresponding to FeSx). The appearance of Cu2O was not conducive to the activity of Cu-Febm (CuSO4) particles, the formation of Fe0/FeSx structure compensated for the partial loss of Fe/Cu alloy. H•abs was identified as the main active species for TCE degradation by Cu-Febm (CuSO4) bimetals. The Cu-Febm (CuSO4) bimetals has great potential for the removal of chlorinated hydrocarbons in water.