Modified kinetic models for Cr (VI) adsorption in polymer inclusion membranes

Abstract

Hexavalent chromium is a highly toxic environmental inorganic pollutant. To eliminate toxic Cr (VI) ions in natural waters, polymer inclusion membranes (PIMs) have been developed for highly selective metal ion transport applications. The investigation of the effectiveness of Cr (VI) recovery in aqueous solutions using PIMs with varying amounts of plasticizer was studied. The pseudo-first order (PFO) kinetic model was modified to describe the amount of Cr (VI) ions that have accumulated onto the PIMs at a specific time and to evaluate the performance of the PIMs. A quantitative analysis of the modified PFO a model based on their non-linear representation and using the coefficient of determination indicates that the adsorptive properties of the PIMs are best described by the modified non-linear pseudo-first-order kinetic model (R2 > 0.9748), suggesting that the sorption process is physisorption. To show the applicability of the modified model to other transport studies, modified PFO was fitted into the experimental data that studies the transport of Zn (II) ions onto PIM (R2 > 0.95).