Synthesis of a new ion-imprinted polymer for selective Cr(VI) adsorption from aqueous solutions effectively and rapidly.

ABSTRACT

Removing hexavalent chromium (Cr(VI)) from aqueous solution is strategically important. A novel and selective adsorbent was synthesized using a high electron beam irradiation pre-grafting and post-surface ion imprinting method using Cr(VI) and polypropylene (PP) fibers as the template and substrates, respectively. The results obtained using Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TG) indicated that the prepared sorbent was successfully synthesized. At the same time, the adsorption performances were studied through batch experiments. The results exhibited rapid adsorption kinetics, a wide working pH range, and excellent selectivity and regeneration. The equilibrium adsorption was achieved within 30 min, the maximum sorption capacity of Cr(VI)-IIPs was 156.5 mg g-1 and partition coefficients (PC) was 0.591 mg g-1 uM-1 at 400 mg L-1 initial concentration and 298 K. The relative selectivity coefficients of the ion-imprinted polymer (IIP) for Cr2O72-/HPO42- and Cr2O72-/NO3- were 36.7 and 39.9, respectively. In addition, the prepared sorbent has a negligible loss in adsorption capacity after five cycles. IIP has good application prospects in the selective removal of Cr(VI) ions.