title: Adsorption characteristics of Pb(II) from aqueous solutions onto a natural biosorbent, fallen arborvitae leaves.
abstract: In this study, the potential of the oriental arborvitae leaves for the adsorption of Pb(II) from aqueous solutions was evaluated. Brunauer-Emmett-Teller analysis showed that the surface area of arborvitae leaves was 29.52 m(2)/g with pore diameter ranging from 2 to 50 nm. X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy showed C-C or C-H, C-O, and O-C=O were the main groups on the arborvitae leaves, which were the main sites for surface complexation. Finally, effects of adsorbent dose, initial pH, contact time, and coexisting natural organic matters (humic acid (HA)) on the adsorption of Pb(II) were investigated. The results indicated that the pHZPC (adsorbents with zero point charge at this pH) was 5.3 and the adsorption reached equilibrium in 120 min. Isotherm simulations revealed that the natural arborvitae leaves exhibit effective adsorption for Pb(II) in aqueous solution, giving adsorptive affinity and capacity in an order of 'no HA' > 5 mg/L HA > 10 mg/L HA, and according to the Langmuir models, the maximum adsorptions of Pb(II) were 43.67 mg/g, 38.61 mg/g and 35.97 mg/g, respectively. The results demonstrated that the oriental arborvitae leaves showed high potentials for the adsorption of Pb(II) from aqueous solutions.
authors.affiliation: Department of National Defense Architecture Planning and Environmental Engineering, Logistical Engineering University, Chongqing 401311, China E-mail: hit_zzw@163.com.
authors.forename: Jie
authors.initials: J
authors.lastname: Shi
authors.affiliation: Department of National Defense Architecture Planning and Environmental Engineering, Logistical Engineering University, Chongqing 401311, China E-mail: hit_zzw@163.com.
authors.forename: Zhiwei
authors.initials: Z
authors.lastname: Zhao
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
authors.forename: Zhijie
authors.initials: Z
authors.lastname: Liang
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
authors.forename: Tianyi
authors.initials: T
authors.lastname: Sun
mesh_terms: D000327:Adsorption; D006812:Humic Substances; D006863:Hydrogen-Ion Concentration; D007854:Lead / Q000737:chemistry*; D018515:Plant Leaves / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D029783:Thuja / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D006812:Humic Substances; D014874:Water Pollutants, Chemical; D007854:Lead