TY - JOUR
T1 - Enhanced adsorption of aqueous Pb(II) by modified biochar produced through pyrolysis of watermelon seeds
AU - Ahmed, Waqas
AU - Mehmood, Sajid
AU - Núñez-Delgado, Avelino
AU - Ali, Sehrish
AU - Qaswar, Muhammad
AU - Shakoor, Awais
AU - Mahmood, Mohsin
AU - Chen, Di-Yun
PY - 2021
Y1 - 2021
N2 - A biochar (BC) was obtained by the pyrolysis of watermelon seeds (WM) in nitrogen environment. In addition, a modified biochar (HP-BC) was obtained by means of H2O2 treatment of BC. Later on, both kinds of biochar (BC and HP-BC) were characterized and compared as regards their potential for Pb(II) adsorption from wastewater. Characterization was performed by using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), energy dispersive spectroscopy (EDS), Zeta potential analysis, elemental mapping, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Pb(II) adsorption characteristics for HP-BC and BC as were evaluated as a function of solution pH, contact time and Pb(II) equilibrium concentration, using kinetic and thermodynamic studies, as well as adsorption isotherms. Regarding kinetics, the pseudo-second order model showed good fitting to experimental data. Based on the Langmuir model, the maximum Pb(II) adsorption capacities were calculated as 44.32 mg g−1 and 60.87 mg g−1 for BC and HP-BC, respectively. Thermodynamic study indicated that Pb(II) adsorption onto BC and HP-BC was spontaneous and primarily governed by chemisorption and surface complexation. In view of the results, the H2O2 modification of the watermelon seeds biochar can be considered as a promising and cost effective approach as regards Pb(II) removal from water/wastewater, which would not cause adverse impacts on the surrounding environments. Overall, it can be seen as a procedure promoting the effective recycling of a waste/by-product, in line of the precepts of the circular economy, aiding to protect human and environmental health.
AB - A biochar (BC) was obtained by the pyrolysis of watermelon seeds (WM) in nitrogen environment. In addition, a modified biochar (HP-BC) was obtained by means of H2O2 treatment of BC. Later on, both kinds of biochar (BC and HP-BC) were characterized and compared as regards their potential for Pb(II) adsorption from wastewater. Characterization was performed by using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), energy dispersive spectroscopy (EDS), Zeta potential analysis, elemental mapping, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Pb(II) adsorption characteristics for HP-BC and BC as were evaluated as a function of solution pH, contact time and Pb(II) equilibrium concentration, using kinetic and thermodynamic studies, as well as adsorption isotherms. Regarding kinetics, the pseudo-second order model showed good fitting to experimental data. Based on the Langmuir model, the maximum Pb(II) adsorption capacities were calculated as 44.32 mg g−1 and 60.87 mg g−1 for BC and HP-BC, respectively. Thermodynamic study indicated that Pb(II) adsorption onto BC and HP-BC was spontaneous and primarily governed by chemisorption and surface complexation. In view of the results, the H2O2 modification of the watermelon seeds biochar can be considered as a promising and cost effective approach as regards Pb(II) removal from water/wastewater, which would not cause adverse impacts on the surrounding environments. Overall, it can be seen as a procedure promoting the effective recycling of a waste/by-product, in line of the precepts of the circular economy, aiding to protect human and environmental health.
UR - https://hdl.handle.net/1959.7/uws:71512
U2 - 10.1016/j.scitotenv.2021.147136
DO - 10.1016/j.scitotenv.2021.147136
M3 - Article
SN - 0048-9697
VL - 784
JO - Science of the Total Environment
JF - Science of the Total Environment
M1 - 147136
ER -
