title: Removal of chromium (VI) from water using nanoscale zerovalent iron particles supported on herb-residue biochar.
abstract: A composite material consisting of nanoscale zerovalent iron particles supported on herb-residue biochar (nZVI/BC) was synthesized and used for treatment of Cr(VI)-contaminated water. The effects of initial pH, chromium concentration, contact time, and competition with coexisting anions and natural organic matter (NOM) were also investigated. nZVI/BC was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy analysis (SEM), and the Brunauer-Emmett-Teller surface area was measured. TEM and X-ray photoelectron spectroscopy (XPS) analysis before and after reaction with Cr(VI) showed that reduction and coprecipitation occurred during hexavalent chromium adsorption. The removal of Cr(VI) was highly pH-dependent and the adsorption kinetics data agreed well with the pseudo-second-order model. The presence of SO42-and humic acid promoted Cr(VI) removal at both low and high concentrations, while the HCO3-inhibited the reaction. These results prove that nZVI/BC can be an effective reagent for removal of Cr(VI) from solutions.
authors.affiliation: School of Engineering, China Pharmaceutical University, Nanjing, 211198, China.
authors.forename: Jingge
authors.initials: J
authors.lastname: Shang
authors.affiliation: School of Engineering, China Pharmaceutical University, Nanjing, 211198, China.
authors.forename: Mingzhu
authors.initials: M
authors.lastname: Zong
authors.affiliation: School of Engineering, China Pharmaceutical University, Nanjing, 211198, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Yu
authors.affiliation: School of Engineering, China Pharmaceutical University, Nanjing, 211198, China.
authors.forename: Xiangrui
authors.initials: X
authors.lastname: Kong
authors.affiliation: School of Engineering, China Pharmaceutical University, Nanjing, 211198, China. Electronic address: duqiong116@163.com.
authors.forename: Qiong
authors.initials: Q
authors.lastname: Du
authors.affiliation: School of Engineering, China Pharmaceutical University, Nanjing, 211198, China. Electronic address: liaoqianjiahua@163.com.
authors.forename: Qianjiahua
authors.initials: Q
authors.lastname: Liao
mesh_terms: D002606:Charcoal; D002857:Chromium; D007501:Iron; D014867:Water; D014874:Water Pollutants, Chemical
chemical_list: D014874:Water Pollutants, Chemical; C540010:biochar; D014867:Water; D002857:Chromium; D002606:Charcoal; C074702:chromium hexavalent ion; D007501:Iron
keywords: Biochar; Co-precipitation; Herb residue; Hexavalent chromium; Nanoscale zerovalent iron