Clean and facile solution synthesis of iron(III)-entrapped gamma-alumina nanosorbents for arsenic removal

Abstract

Iron(III)-entrapped gamma-alumina nanosorbents were prepared by an environmentally benign method using an ionothermal process based on an ionic liquid to synthesize the gamma-alumina host and a sonochemical method to entrap the iron(III) guest. The morphology of the alumina depends on the aluminum precursor used, giving aligned bundled and randomly debundled gamma-alumina nanorods as well as wormlike mesoporous alumina. In particular the rodlike structure shows significantly greater mesoporosity than the wormlike porous gamma-alumino structure. Moreover entrapment of iron(III) in the gamma-alumino nanosorbents with randomly debundled rodlike structures leads to the greatest As(V) removal capacity and the fastest adsorption rote as compared to the other Fe(III)-entrapped adsorbents, as a result of its larger surface area and pore sizes. Thus, this method provides a clean and effective route to an advanced host-guest adsorbent system for application in the removal of arsenic from drinking water.