Radiation synthesis and Cr(VI) removal of cellulose microsphere adsorbent

A novel cellulose-based adsorbent was prepared by radiation-induced grafting of styrene onto the surface of cellulose microspheres, followed by acetylation and amination processes. The grafting yield was adjusted by the total absorbed dose, dose rate and the concentration of styrene. The structure of the adsorbent was characterized by micro-FTIR, XPS and SEM. The adsorption of Cr(VI) ions has been investigated as a function of contact time, adsorbent feed, pH, Cr(VI) and NaCl concentration. It was found that adsorption equilibrium could be achieved within 30 min for initial Cr(VI) of 100 mg L−1. The adsorption kinetics was well described by the pseudo-second order model equation, and the adsorption isotherm was better fitted by the Langmuir mode. The maximum theoretical Cr(VI) uptake of the adsorbent was 123.4 mg g−1. The influence of NaCl concentration on Cr(VI) uptake and XPS analysis revealed that Cr(VI) ions were adsorbed through ion-exchange mechanism.