TY - JOUR

T1 - Novel Fe-Mn binary oxide-biochar as an adsorbent for removing Cd(II) from aqueous solutions

AU - Yin, Guangcai

AU - Song, Xiaowang

AU - Tao, Lin

AU - Sarkar, Binoy

AU - Sarmah, Ajit K

AU - Zhang, Wenxiang

AU - Lin, Qintie

AU - Xiao, Rongbo

AU - Liu, Qianjun

AU - Wang, Hailong

N1 - This is the author’s version of a work that was accepted for publication in Chemical Engineering Journal. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Chemical Engineering Journal, 389, 2020 DOI: 10.1016/j.cej.2020.124465

PY - 2020/6/1

Y1 - 2020/6/1

N2 - In this study, a pristine biochar (BC) and Fe-Mn binary oxide-biochar (FMBC) were prepared using Pennisetum sp. straw as the feedstock for Cd(II) removal from aqueous solutions. Scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and specific surface area (SSA) analyses revealed the physico-chemical characteristics of the pristine and designer adsorbents, suggesting that an ultrasonic treatment during synthesis enhanced the SSA and pore volume of the BC, and assisted successful loading of Fe-Mn binary oxide particles on the BC surface. The Cd(II) adsorption data of the adsorbents were fitted to the Langmuir isothermal and pseudo-second-order kinetic models. At a system temperature of 25 °C and pH 5, the maximum Cd(II) adsorption capacities of BC (30.58 mg/g) and FMBC (95.23 mg/g) were obtained. Multiple Cd(II) adsorption mechanisms by FMBC were identified, including precipitation with minerals, complexation with surface functional groups, Cd(II)-π interactions, and cation exchange. As the most dominant adsorption mechanism, Cd-O bonds were formed on the FMBC surfaces precipitating Cd(OH)2 (63.9 wt%) and CdO (36.1 wt%). The FMBC thus could be potentially used as an effective adsorbent for Cd(II) removal from aqueous solutions.

AB - In this study, a pristine biochar (BC) and Fe-Mn binary oxide-biochar (FMBC) were prepared using Pennisetum sp. straw as the feedstock for Cd(II) removal from aqueous solutions. Scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and specific surface area (SSA) analyses revealed the physico-chemical characteristics of the pristine and designer adsorbents, suggesting that an ultrasonic treatment during synthesis enhanced the SSA and pore volume of the BC, and assisted successful loading of Fe-Mn binary oxide particles on the BC surface. The Cd(II) adsorption data of the adsorbents were fitted to the Langmuir isothermal and pseudo-second-order kinetic models. At a system temperature of 25 °C and pH 5, the maximum Cd(II) adsorption capacities of BC (30.58 mg/g) and FMBC (95.23 mg/g) were obtained. Multiple Cd(II) adsorption mechanisms by FMBC were identified, including precipitation with minerals, complexation with surface functional groups, Cd(II)-π interactions, and cation exchange. As the most dominant adsorption mechanism, Cd-O bonds were formed on the FMBC surfaces precipitating Cd(OH)2 (63.9 wt%) and CdO (36.1 wt%). The FMBC thus could be potentially used as an effective adsorbent for Cd(II) removal from aqueous solutions.

KW - Water treatment

KW - Adsorption mechanism

KW - Havy metal removal

KW - Designer biochars

U2 - 10.1016/j.cej.2020.124465

DO - 10.1016/j.cej.2020.124465

M3 - Journal article

VL - 389

JO - Chemical Engineering Journal

JF - Chemical Engineering Journal

SN - 1385-8947

M1 - 124465

ER -