Selective uranium sorption from salt lake brines by amidoximated Saccharomyces cerevisiae

Abstract

In order to enhance the selectivity of Saccharomyces cerevisiae for uranium, amidoximation of the biomass was performed. The obtained biosorbent was characterized by FTIR and SEM analysis, results showed that amidoxime groups were successfully grafted on the biomass surface. The effects of initial solution pH, time, initial uranium concentration and ion strength on uranium sorption by the amidoximated biomass were studied and the optimal sorption conditions were determined. Furthermore, desorption results revealed that the amidoximated biosorbent can be used at least three times. The uranium sorption kinetics of both amidoximated and raw biomass can be depicted by the nonlinear pseudo-second-order kinetic equation. The nonlinear Langmuir and Freundlich models fitted well with the equilibrium data of amidoximated biomass. Trace uranium sorption from salt lake brine samples suggested that the selectivity of S. cerevisiae was obvious enhanced after amidoximation. The prepared amidoximated biomass can be used as a potential sorbent for selective uranium recovery from salt lake brines.