Effective dechlorination of HCB by nanoscale Cu/Fe particles.
We previously reported that microscale Cu/Fe bimetal could be used for the dechlorination of hexachlorobenzene (HCB), a representative polychlorinated persistent organic pollutant (POPs). But slow reduction rate and rather incomplete dechlorination were reached. In this study, HCB dechlorination by nanoscale Fe and Cu/Fe was evaluated. It was found that HCB reduction by nanoscale Fe was rather slow, and the reduction was significantly increased by nanoscale Cu/Fe. Near complete reduction of HCB was obtained by nanoscale Cu/Fe for 48 h treatment. HCB was quickly dechlorinated to PeCB, TeCBs, TCBs and DCBs without selectivity via a stepwise process. The reduction rate and dechlorination extent were much higher compared with microscale Cu/Fe. Lowering pH during reduction showed slightly negative influence on HCB reduction by nanoscale Cu/Fe due to retarded co-precipitation. A catalytic hydrogenation process on Cu surface through iron oxide film was suggested for the increased HCB reduction by Cu coating on nanoscale Fe. This study proved that using a much cheaper bimetallic iron of nanoscale Cu/Fe than nanoscale Pd/Fe could also achieve the effective dechlorination of HCB.
Zhu
Nairuo
N
Environmental Science Research Institute, Huazhong University of Science and Technology, Wuhan 430074, PR China.
Luan
Hongwei
H
Yuan
Songhu
S
Chen
Jing
J
Wu
Xiaohui
X
Wang
Linling
L
D003300:Copper / Q000737:chemistry*; D054879:Halogenation; D006581:Hexachlorobenzene / Q000737:chemistry*; D006843:Hydrocarbons, Chlorinated / Q000737:chemistry; D006865:Hydrogenation; D007501:Iron / Q000737:chemistry*; D007700:Kinetics; D053768:Metal Nanoparticles / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry*
D006843:Hydrocarbons, Chlorinated; D014874:Water Pollutants, Chemical; D006581:Hexachlorobenzene; D003300:Copper; D007501:Iron