TY - JOUR
T1 - Investigating the adsorption behavior and quantitative contribution of Pb2+ adsorption mechanisms on biochars by different feedstocks from a fluidized bed pyrolysis system
AU - Liu, Lingqin
AU - Huang, Yaji
AU - Meng, Yuanhua
AU - Cao, Jianhua
AU - Hu, Huajun
AU - Su, Yinhai
AU - Dong, Lu
AU - Tao, Shengnian
AU - Ruan, Roger
N1 - Publisher Copyright:
© 2020 Elsevier Inc.
PY - 2020/8
Y1 - 2020/8
N2 - The aim of this study was to examine the qualitative and quantitative analysis of Pb2+ adsorption mechanisms performed with biochars derived from rice straw (RSBs), rice husk (RHBs) and saw dust (SDBs) at several pyrolysis temperatures (400-600 °C) in a fluidized bed system. Adsorption isotherms, kinetics, and desorption analysis were determined, and biochars were analyzed by X-ray Photoelectron Spectroscopy (XPS), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscope with Energy Dispersive Spectrometer (SEM-EDS) and Boehm titration method. The effect of minerals on Pb2+ adsorption, including precipitation and cation exchange, revealed increasing contribution of precipitation from a range of 4.13%–38.83% to a range of 34.08%–79.94% and decreasing effect of cation exchange from a range of 50.17%–69.75% to a range of 9.57%–43.47% with increasing pyrolysis temperature. However, it remained the dominant adsorption mechanism of all biochars (accounted for 69.49–89.52%). Especially, RSBs with quite high maximum adsorption capacity (qm) values (116-127.57 mg[rad]g−1) were mainly due to precipitation mechanism of Pb2+ adsorption, which exhibited better adsorption capacities than RHBs (25.15–30.40 mg[rad]g−1) and SDBs (21.81–24.05 mg[rad]g−1). Only with the fluidized bed shown in this study, 2.00t RSBs could be produced and the corresponding Pb2+ adsorption may reach 255.50kg per year depending on its maximum adsorption capacity under 500 °C pyrolysis temperature. The results suggest that RSBs produced in a fluidized bed reactor is a promising, cost-effective, engineered biochar for application of Pb2+ remediation in aqueous solutions.
AB - The aim of this study was to examine the qualitative and quantitative analysis of Pb2+ adsorption mechanisms performed with biochars derived from rice straw (RSBs), rice husk (RHBs) and saw dust (SDBs) at several pyrolysis temperatures (400-600 °C) in a fluidized bed system. Adsorption isotherms, kinetics, and desorption analysis were determined, and biochars were analyzed by X-ray Photoelectron Spectroscopy (XPS), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscope with Energy Dispersive Spectrometer (SEM-EDS) and Boehm titration method. The effect of minerals on Pb2+ adsorption, including precipitation and cation exchange, revealed increasing contribution of precipitation from a range of 4.13%–38.83% to a range of 34.08%–79.94% and decreasing effect of cation exchange from a range of 50.17%–69.75% to a range of 9.57%–43.47% with increasing pyrolysis temperature. However, it remained the dominant adsorption mechanism of all biochars (accounted for 69.49–89.52%). Especially, RSBs with quite high maximum adsorption capacity (qm) values (116-127.57 mg[rad]g−1) were mainly due to precipitation mechanism of Pb2+ adsorption, which exhibited better adsorption capacities than RHBs (25.15–30.40 mg[rad]g−1) and SDBs (21.81–24.05 mg[rad]g−1). Only with the fluidized bed shown in this study, 2.00t RSBs could be produced and the corresponding Pb2+ adsorption may reach 255.50kg per year depending on its maximum adsorption capacity under 500 °C pyrolysis temperature. The results suggest that RSBs produced in a fluidized bed reactor is a promising, cost-effective, engineered biochar for application of Pb2+ remediation in aqueous solutions.
KW - Adsorption mechanisms
KW - Biochar
KW - Fluidized bed pyrolysis
KW - Lead
KW - Quantitative contribution
KW - Pyrolysis
KW - Adsorption
KW - Charcoal
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U2 - 10.1016/j.envres.2020.109609
DO - 10.1016/j.envres.2020.109609
M3 - Article
C2 - 32450423
AN - SCOPUS:85085045629
SN - 0013-9351
VL - 187
JO - Environmental Research
JF - Environmental Research
M1 - 109609
ER -