Adsorption of Uranium(VI) from a Simulated Saline Solution by Alkali-Activated Leather Waste

Abstract

A porous adsorbent was prepared from leather waste by activation with alkali. The adsorbent, alkali-activated leather waste (AALW), was applied to adsorb uranium(VI) and characterized by scanning electron microscopy, energy-dispersive X-ray detection, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The influence of the pH, initial uranium(VI) concentration, temperature, and contact time on the adsorption of uranium(VI) was systematically investigated. The adsorption of uranium(VI) on AALW obeyed the Langmuir isotherm model and was attributed to ion exchange and complexation coordination. Thermodynamic and kinetic studies showed that the adsorption process was spontaneous and endothermic, and it reached adsorption equilibrium in 360 min. Moreover, the selective adsorption of uranium(VI) from an aqueous solution containing coexisting ions and adsorption of trace uranium(VI) from a simulated high-salinity environment showed that AALW had not only a strong affinity but a high se...