title: Excellently reactive Ni/Fe bimetallic catalyst supported by biochar for the remediation of decabromodiphenyl contaminated soil: Reactivity, mechanism, pathways and reducing secondary risks.
abstract: Ni/Fe bimetallic nanoparticles were synthesized using biochar as a support (BC@Ni/Fe) and their effectiveness in removing BDE209 from soil was investigated. BET, SEM, TEM, XPS and FTIR were used to characterize the catalyst, and the efficiencies of biochar, Ni/Fe nanoparticles and BC@Ni/Fe for removing BDE209 from soil were compared. The results showed that Ni/Fe bimetallic nanoparticles highly dispersed in the biochar, reducing its agglomeration. Thus, the reaction activity of BC@Ni/Fe was increased. The removal efficiency of BDE209 by BC@Ni/Fe was 30.2% and 69% higher than that by neat Ni/Fe and biochar, respectively. Meanwhile, an enhanced degradation efficiency of PBDEs in soil was realized by monitoring the formation of Br-ions with time in the system. In addition, the degradation products identified by GC-MS showed that the reductive degradation of BDE209 proceeded through stepwise or multistage debromination, for which the degradation pathways and removal mechanisms were speculated. Furthermore, BC@Ni/Fe reduced the bioavailability of metals in soil and adsorbed the degradation products of BDE209, representing an improvement over neat Ni/Fe nanoparticles for the remediation of PBDEs-contaminated soil.
authors: School of Chemistry and Environment, South China Normal University, Guangzhou 510006, China; Guangdong Technology Research Centre for Ecological Management and Remediation of Water System, Guangzhou 510006, China.
authors: Juan
authors: J
authors: Wu
authors: School of Chemistry and Environment, South China Normal University, Guangzhou 510006, China; Guangdong Technology Research Centre for Ecological Management and Remediation of Water System, Guangzhou 510006, China.
authors: YunQiang
authors: Y
authors: Yi
authors: South China institute of Environmental Science, Guangzhou 510655, China.
authors: YuQing
authors: Y
authors: Li
authors: School of Chemistry and Environment, South China Normal University, Guangzhou 510006, China; Guangdong Technology Research Centre for Ecological Management and Remediation of Water System, Guangzhou 510006, China. Electronic address: sunmoon124@163.com.
authors: Zhanqiang
authors: Z
authors: Fang
authors: Department of Science and Environmental Studies, The Hong Kong Institute of Education, Hong Kong 00852, China.
authors: Eric Pokeung
authors: EP
authors: Tsang
keywords: BDE209; Biochar-supported Ni/Fe bimetallic nanoparticles; Remediation; Risk assessment; Soil