Sorption performance and mechanisms of arsenic(V) removal by magnetic gelatin-modified biochar

A new environmentally friendly and low-cost adsorbent to remove As(V) from industry waste water was synthesized by the mixture of 723 K pyrolyzed chestnut shell and magnetic gelatin. The resultant biochar was characterized by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), Fourier transform infrared spectrometer (FT-IR) and vibrating sample magnetometer (VSM). Magnetic gelatin microsphere enlarged the specific surface area of pristine biochar so the modified biochar had more adsorption sites for arsenic(V) removal. Also, it had strong magnetic property so it could be easily separated from aqueous solution. Batch sorption experiment results showed that the maximum adsorption capacity was 45.8 mg g−1, which was higher than that of the unmodified (17.5 mg g−1) and some other biochar. All findings illustrated that this new material could be used to deal with arsenic(V)-containing waste water effectively.