Surface characteristics of a recyclable and efficient adsorption material

Magnetized biochar materials (MCs) were prepared through magnetization of biochar (C) by Fe3O4-loaded coprecipitation method and coating the MCs with different ratios of the amphoteric modifier, dodecyl dimethyl betaine (BS-12), for C recycling and simultaneous adsorption of various pollutants. The MC and BS-12-coated MCs (BS-MCs) were subjected to characterization methods, such as scanning electron microscopy (SEM), thermogravimetry (TG), vibrating sample magnetometry (VSM), and Fourier transform infrared (FT-IR) spectroscopy. Results indicated the following. (1) With increased BS-12 coating ratio, the pH, cation exchange capacity (CEC) and specific surface areas (S-BET) of each BS-MC decreased gradually. (2) BS-MCs exhibited good magnetic separation performance, and their infrared spectra showed that Fe3O4 and BS-12 had been loaded on the C surface. The TG curves showed that the weight loss rate of BS-MC increased with increasing BS-12 coating ratio. (3) According to SEM results, Fe3O4 was evenly distributed on C, and no evident agglomeration was observed. After BS-12 coating, BS-MCs presented lower surface roughness and higher concentration of particles, which confirmed that BS-12 coated the MCs organically. (C) 2019 Published by Elsevier B.V.