title: Nonionic surfactant greatly enhances the reductive debromination of polybrominated diphenyl ethers by nanoscale zero-valent iron: mechanism and kinetics.
abstract: Nanoscale zero-valent iron (nZVI) has been considered as an effective agent for reductive debromination of polybrominated diphenyl ethers (PBDEs). But the high lipophilicity of PBDEs will hinder their debromination owing to the inefficient contact of PBDEs with nZVI. In this study, different ionic forms of surfactants were investigated aiming to promote PBDE debromination, and the beneficial effects of surfactant were found to be: nonionic polyethylene glycol octylphenol ether (Triton X-100, TX)>cationic cetylpyridinium chloride (CPC)>anionic sodium dodecyl benzenesulfonate (SDDBS). Except for with SDDBS, the promotion effect for PBDE debromination was positively related to the surfactant concentrations until a critical micelle concentration (CMC). The debromination process of octa-BDE and its intermediates could be described as a consecutive reaction. The corresponding rate constants (k) for the debromination of parent octa-BDE (including nona- to hepta-BDEs), the intermediates hexa-, penta-, and tetra-BDEs are 1.24 × 10(-1) h(-1), 8.97 × 10(-2) h(-1), 6.50 × 10(-2) h(-1) and 2.37 × 10(-3) h(-1), respectively.
authors.affiliation: School of Chemistry & Environment, Beihang University (BUAA), 37 Xueyuan Rd, Beijing 100191, China.
authors.forename: Da-wei
authors.initials: DW
authors.lastname: Liang
authors.affiliation: School of Chemistry & Environment, Beihang University (BUAA), 37 Xueyuan Rd, Beijing 100191, China.
authors.forename: Yu-han
authors.initials: YH
authors.lastname: Yang
authors.affiliation: School of Chemistry & Environment, Beihang University (BUAA), 37 Xueyuan Rd, Beijing 100191, China.
authors.forename: Wei-wei
authors.initials: WW
authors.lastname: Xu
authors.affiliation: School of Chemistry & Environment, Beihang University (BUAA), 37 Xueyuan Rd, Beijing 100191, China.
authors.forename: Si-kan
authors.initials: SK
authors.lastname: Peng
authors.affiliation: School of Chemistry & Environment, Beihang University (BUAA), 37 Xueyuan Rd, Beijing 100191, China.
authors.forename: Shan-fu
authors.initials: SF
authors.lastname: Lu
authors.affiliation: School of Chemistry & Environment, Beihang University (BUAA), 37 Xueyuan Rd, Beijing 100191, China. Electronic address: xiangy@buaa.edu.cn.
authors.forename: Yan
authors.initials: Y
authors.lastname: Xiang
mesh_terms: D001557:Benzenesulfonates / Q000737:chemistry; D001966:Bromine / Q000737:chemistry*; D002594:Cetylpyridinium / Q000737:chemistry; D055768:Halogenated Diphenyl Ethers / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D007700:Kinetics; D053758:Nanoparticles / Q000737:chemistry; D017830:Octoxynol / Q000737:chemistry; D010084:Oxidation-Reduction; D013501:Surface-Active Agents / Q000737:chemistry*
chemical_list: D001557:Benzenesulfonates; D055768:Halogenated Diphenyl Ethers; D013501:Surface-Active Agents; C001114:dodecylbenzenesulfonic acid; D017830:Octoxynol; D002594:Cetylpyridinium; D007501:Iron; D001966:Bromine
keywords: Degradation kinetics; Nanoscale zero-valent iron (nZVI); Polybrominated biphenyl ether (PBDE); Reductive debromination; Surfactants