title: Nanoscale zero-valent iron supported by biochars produced at different temperatures: Synthesis mechanism and effect on Cr(VI) removal.
abstract: Biochar-supported nanoscale zero-valent iron (nZVI) produced under different temperatures was studied to evaluate the effect of the nZVI-biochar composite on the removal of hexavalent chromium (Cr(VI)) in solution. The structure of biochar-supported nZVI and its roles in Cr(VI) removal were investigated by X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and batch experiments. The XRD revealed that the removal rate of Cr(VI) for the nZVI supported by rice straw pyrolyzed at 400 °C (RS400) was much greater than that for other supporting biochar, and the FTIR further indicated that the carboxyl groups and silicon mineral within the biochar served as dual support sites for nZVI. NZVI-RS400 exhibited the highest removal amount of Cr(VI) at approximately 40.0 mg/g under an initial pH of 4.0, possibly due to both the reduction and adsorption processes. Therefore, the RS400-supported nanoscale zero-valent iron could be a preferable material for Cr(VI)-contaminated groundwater.
authors.affiliation: Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, Jiangsu Province, China.
authors.forename: Linbo
authors.initials: L
authors.lastname: Qian
authors.affiliation: Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, Jiangsu Province, China.
authors.forename: Wenying
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, Jiangsu Province, China.
authors.forename: Jingchun
authors.initials: J
authors.lastname: Yan
authors.affiliation: Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, Jiangsu Province, China.
authors.forename: Lu
authors.initials: L
authors.lastname: Han
authors.affiliation: Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, Jiangsu Province, China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, Jiangsu Province, China.
authors.forename: Da
authors.initials: D
authors.lastname: Ouyang
authors.affiliation: Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, Jiangsu Province, China. Electronic address: mfchen@issas.ac.cn.
authors.forename: Mengfang
authors.initials: M
authors.lastname: Chen
mesh_terms: D000327:Adsorption; D002606:Charcoal / Q000737:chemistry*; D002857:Chromium / Q000737:chemistry*; D052918:Environmental Restoration and Remediation; D060587:Groundwater / Q000737:chemistry; D007501:Iron / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D013696:Temperature; D014874:Water Pollutants, Chemical / Q000032:analysis; D014961:X-Ray Diffraction
chemical_list: D014874:Water Pollutants, Chemical; C540010:biochar; D002857:Chromium; D002606:Charcoal; C074702:chromium hexavalent ion; D007501:Iron
keywords: Adsorption; Biochars; Hexavalent chromium; Nanoscale zero-valent iron; Reduction