title: [Dechlorination of HCB by bimetals based on zero valent iron].
abstract: Based on the reducing capacity of zero valent iron, the study investigated the behavior of dechlorination of hexachlorobenzene by bimetals synthetized using Fe with Ag, Pb or Cu as catalysts, respectively. The results showed that bimetals could dechlorinate HCB faster than Fe(0) did, the optimal ratios of Ag/Fe, Pb/Fe and Cu/Fe were 0.2%, 0.5% and 1%. After reacting 2 hours, the dechlorination rates of HCB by Ag/Fe, Pb/Fe and Cu/Fe were 93.5%, 88.5% and 49.6% respectively. The catalyst metal distribution had a great effect on the reductive dechlorination capacity of the bimetal systems, due to more galvanic cells produced by well-distributed catalyst metal and iron. Increasing the amount of bimetal was an effective way to promote HCB dechlorination rate, 88.6% HCB was degraded in 2 h by 0.8 g Pb/Fe while only 38.3% HCB was degraded by 0.1 g Pb/Fe. Besides, HCB dechlorination could be enhanced a little with increasing ionic strength, the HCB dechlorination rates were 93.5%, 98.0% and 98.9% respectively with Na2SO4 concentration at 0, 0.05 and 0.5 mol x L(-1).
authors.affiliation: School of Environment, Tsinghua University, Beijing 100084, China. zengxianweioo@163.com
authors.forename: Xian-Wei
authors.initials: XW
authors.lastname: Zeng
authors.forename: Jian-Guo
authors.initials: JG
authors.lastname: Liu
authors.forename: Xiao-Qin
authors.initials: XQ
authors.lastname: Nie
mesh_terms: D002384:Catalysis; D003300:Copper / Q000737:chemistry; D004785:Environmental Pollutants / Q000737:chemistry / Q000302:isolation & purification*; D054879:Halogenation; D006581:Hexachlorobenzene / Q000737:chemistry / Q000302:isolation & purification*; D007501:Iron / Q000737:chemistry*; D007854:Lead / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry*; D012834:Silver / Q000737:chemistry
chemical_list: D004785:Environmental Pollutants; D007854:Lead; D012834:Silver; D006581:Hexachlorobenzene; D003300:Copper; D007501:Iron