Sorption of cobalt (II) and chromium (III) ions to nitrogen- and sulfur-containing polyampholyte on the basis of polyvinylchloride

In this article, we studied the process of obtaining nitrogen- and sulfur-containing polyampholyte by chemical modification of sulphocation exchanger. Which is synthesized based on polyvinyl chloride (PVC), with polyethylenepolyamine. Besides, the PVC and synthesized ion exchange resins were characterized using different tools such as FT-IR, scanning electron microscope, and energy-dispersive X-ray. Moreover, the synthesized polyampholyte was used as effective adsorbents for removing Co (II) and Cr (III) ions from aqueous solutions. The Freundlich isotherm and the pseudo-second order kinetic model were more consistent with the removal of metal ions from aqueous solutions. In the case of Co (II) and Cr (III), the maximum adsorption capacity was 3.45 and 3.97 mmol g(-1), respectively. The thermodynamic parameters of the sorption process of metal ions such as free energy (Delta G), enthalpy (Delta H), and entropy (Delta S) of the system were calculated. Furthermore, we find that the adsorption processes were spontaneous and chemisorption.