Synthesis of peanut shell based magnetic activated carbon with excellent adsorption performance towards electroplating wastewater

A novel peanut shell based magnetic activated carbon (MPAC) with remarkably enhanced adsorption performance towards real electroplating wastewater was successfully synthesized by chemical activation and followed hydrothermal magnetization. The physicochemical properties of the MPAC, the peanut shell based activated carbon (PAC) without magnetization and a commercial activated carbon (CAC) were comparatively investigated by XRD, BET, SEM and FT-IR. Batch adsorption experiments show that their adsorption processes are well described by the pseudo-second-order kinetic model, and the equilibrium data of the MPAC fit the Langmuir isotherm well with a maximum adsorption capacity of 192.31 mg/g towards Cr(VI). Importantly, the MPAC shows removal rates of 99.97% and 100.00% towards Cr(VI) and Cu(II) of the real electroplating wastewater collected from a factory in Wuhan, respectively; the residual concentrations of Ni and Fe can also meet the quality standard for ground water of China (GB/T 14848-93). The continuous experiment of dynamic adsorption column shows that the saturated adsorption capacity of the MPAC towards Cr(VI) can reach 131.0 mg/g, and it could also be easily separated after adsorption, indicating that it has great potential in dealing with real electroplating wastewater. (C) 2018 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.