Modeling And Optimization Of Removal Of Strontium And Cesium From Aqueous Streams By Size Enhanced Ultrafiltration Using Chitosan Derivative

Treatment of fission product aqueous waste is a challenging problem as their chemical concentrations are too low but have significant radiation hazard due to their half-life. The current methods of co-precipitation lead to more sludge and require more space for confinement. Size enhanced ultrafiltration (SEUF) is an emerging technology with a potential not only to effectively separate the species of interest namely Strontium [Sr(II)] and Cesium [Cs(I)] but also recover them by reversing certain chemical conditions. The present paper concerns the removal of Sr(II) and Cs(I) from aqueous streams using SEUF. The studies were conducted using chitosan derivative, carboxymethyl chitosan (CMCh) as a size enhancing agent. The effect of process variables such as initial pH, loading ratio (P/M), and initial concentration of Sr(II) and Cs(I) on the percentage rejection and binding capacity have been studied. The design of experiments was performed by response surface methodology (RSM). The maximum percentage rejection of Cs(I) was found to be 99% at the following optimum process conditions: initial pH of the feed solution is 12, initial concentration of Cs(I) is 10 mg/L, and P/M value is 0.5. The maximum percentage rejection of Sr(II) was found to be 99% at the following optimum process conditions: initial pH of the feed solution is 12, initial concentration of Sr(II) is 9 mg/L, and P/M value is 0.5. The results show that SEUF with CMCh could be an effective method for the removal of Sr(II) and Cs(I).