Synthesis of magnetic wheat straw for arsenic adsorption

Abstract

Magnetic wheat straw (MWS) with different Fe(3)O(4) content was synthesized by using in-situ co-precipitation method. It was characterized by powder X-ray diffraction (XRD) and vibrating sample magnetometer (VSM). This material can be used for arsenic adsorption from water, and can be easily separated by applied magnetic field. The introduction of wheat straw template highly enhanced the arsenic adsorption of Fe(3)O(4). Among three adsorption isotherm models examined, the data fitted Langmuir model better. Fe(3)O(4) content and initial pH value influenced its adsorption behavior. Higher Fe(3)O(4) content corresponded to a higher adsorption capacity. In the pH range of 3-11, As(V) adsorption was decreased with increasing of pH; As(III) adsorption had the highest capacity at pH 7-9. Moreover, by using 0.1 mol L(-1) NaOH aqueous solution, it could be regenerated. This work provided an efficient way for making use of agricultural waste.