title: Removal of Pb(II) by adsorption onto Chinese walnut shell activated carbon.
abstract: The excessive discharge of Pb(II) into the environment has increasingly aroused great concern. Adsorption is considered as the most effective method for heavy metal removal. Chinese walnut shell activated carbon (CWSAC) was used as an adsorbent for the removal of Pb(II) from aqueous solution. Batch experiments were conducted by varying contact time, temperature, pH, adsorbent dose and initial Pb(II) concentration. Adsorption equilibrium was established within 150 min. Although temperature effect was insignificant, the Pb(II) adsorption was strongly pH dependent and the maximum removal was observed at pH 5.5. The Pb(II) removal efficiency increased with increasing CWSAC dosage up to 2.0 g/L and reached a maximum of 94.12%. Langmuir and Freundlich adsorption isotherms were employed to fit the adsorption data. The results suggested that the equilibrium data could be well described by the Langmuir isotherm model, with a maximum adsorption capacity of 81.96 mg/g. Adsorption kinetics data were fitted by pseudo-first- and pseudo-second-order models. The result indicated that the pseudo-first-order model best describes the adsorption kinetic data. In summary, CWSAC could be a promising material for the removal of Pb(II) from wastewater.
authors.affiliation: Key Laboratory of Functional Organometallic Materials of College of Hunan Province, Department of Chemistry and Material Science, Hengyang Normal University, Hengyang 421008, China; School of Civil and Environmental Engineering, and National 'International Cooperation Base on Environment and Energy', University of Science and Technology Beijing, Beijing 100083, China E-mail: yaojun@ustb.edu.cn.
authors.forename: Zheng-ji
authors.initials: ZJ
authors.lastname: Yi
authors.affiliation: School of Civil and Environmental Engineering, and National 'International Cooperation Base on Environment and Energy', University of Science and Technology Beijing, Beijing 100083, China E-mail: yaojun@ustb.edu.cn.
authors.forename: Jun
authors.initials: J
authors.lastname: Yao
authors.affiliation: Key Laboratory of Functional Organometallic Materials of College of Hunan Province, Department of Chemistry and Material Science, Hengyang Normal University, Hengyang 421008, China.
authors.forename: Yun-fei
authors.initials: YF
authors.lastname: Kuang
authors.affiliation: School of Civil and Environmental Engineering, and National 'International Cooperation Base on Environment and Energy', University of Science and Technology Beijing, Beijing 100083, China E-mail: yaojun@ustb.edu.cn.
authors.forename: Hui-lun
authors.initials: HL
authors.lastname: Chen
authors.affiliation: School of Civil and Environmental Engineering, and National 'International Cooperation Base on Environment and Energy', University of Science and Technology Beijing, Beijing 100083, China E-mail: yaojun@ustb.edu.cn.
authors.forename: Fei
authors.initials: F
authors.lastname: Wang
authors.affiliation: School of Civil and Environmental Engineering, and National 'International Cooperation Base on Environment and Energy', University of Science and Technology Beijing, Beijing 100083, China E-mail: yaojun@ustb.edu.cn.
authors.forename: Zhi-min
authors.initials: ZM
authors.lastname: Yuan
mesh_terms: D000327:Adsorption; D002606:Charcoal / Q000737:chemistry*; D031324:Juglans / Q000737:chemistry*; D007700:Kinetics; D007854:Lead / Q000737:chemistry*; D013696:Temperature; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification
chemical_list: D014874:Water Pollutants, Chemical; D002606:Charcoal; D007854:Lead