title: Pyrolytic temperatures impact lead sorption mechanisms by bagasse biochars.
abstract: The characteristics and mechanisms of Pb sorption by biochars produced from sugarcane bagasse at 250, 400, 500, and 600 °C were examined. The Pb sorption isotherms, kinetics and desorption were investigated. All biochars were effective in Pb sorption and were well described by Langmuir isotherm model and pseudo-second-order kinetic model. The maximum sorption capacity decreased from 21 to 6.1 mg g(-1) as temperature increased from 250 to 600 °C. The Pb sorption was rapid initially, probably controlled by cation exchange and complexation and then slowed down, which might be due to intraparticle diffusions. FTIR data and kinetic models suggested that oxygen functional groups were probably responsible for the high Pb sorption onto low temperature biochars (250 and 400 °C) whereas intraparticle diffusion was mainly responsible for low Pb sorption onto high temperature biochars (500 and 600 °C). Decreased phosphorus concentration indicated that P-induced Pb precipitation was also responsible for Pb sorption. Pyrolysis temperature significantly affected biochar properties and played an important role in Pb sorption capacity and mechanisms by biochars.
authors.affiliation: Department of Environmental Engineering, Chongqing University, Chongqing 400045, China; Department of Soil and Water Science, University of Florida, Gainesville, FL 32611, USA.
authors.forename: Wenchuan
authors.initials: W
authors.lastname: Ding
authors.affiliation: Department of Soil and Water Science, University of Florida, Gainesville, FL 32611, USA.
authors.forename: Xiaoling
authors.initials: X
authors.lastname: Dong
authors.affiliation: Department of Agricultural and Biological Engineering, University of Florida, Gainesville, FL 32611, USA.
authors.forename: Inyang Mandu
authors.initials: IM
authors.lastname: Ime
authors.affiliation: Department of Agricultural and Biological Engineering, University of Florida, Gainesville, FL 32611, USA.
authors.forename: Bin
authors.initials: B
authors.lastname: Gao
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210023, China; Department of Soil and Water Science, University of Florida, Gainesville, FL 32611, USA. Electronic address: lqma@ufl.edu.
authors.forename: Lena Q
authors.initials: LQ
authors.lastname: Ma
mesh_terms: D000327:Adsorption; D002482:Cellulose; D002606:Charcoal / Q000737:chemistry*; D006358:Hot Temperature; D007854:Lead / Q000737:chemistry*; D031786:Saccharum; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification / Q000379:methods
chemical_list: D014874:Water Pollutants, Chemical; C540010:biochar; D002606:Charcoal; D007854:Lead; D002482:Cellulose; C027433:bagasse
keywords: Bagasse biochar; Functional groups; Lead; Pyrolysis temperature; Sorption kinetics