Preparation of a novel chloromethylated polystyrene-2-amino-1,3,4-thiadiazole chelating resin and its adsorption properties and mechanism for separation and recovery of Pt(iv) from aqueous solutions

Abstract

A novel chelating resin, chloromethylated polystyrene beads (PS-Cl) 2-amino-1,3,4-thiadiazole (PS-ATD), with an efficient methodology was synthesized simply by the reaction of chloromethylated polystyrene with 2-amino-1,3,4-thiadiazole. The effects of reaction parameters of PS-ATD resin (reaction solvent, reaction temperature and the molar ratio of reagents and different times) were monitored to specify the best synthesis conditions. The functional group capacity (the content of the functional group) and the percentage conversion of the functional group of PS-ATD resin prepared under optimum conditions were 3.65 mmol g⁻¹ and 88.6%, respectively. The structure of PS-ATD resin was characterized by elemental analysis, FTIR, TGA, SEM, and energy dispersive X-ray spectroscopy (EDS). Meanwhile, the adsorption properties of the resin for Pt(IV) were investigated by batch and column experiments. The results suggested that the resin possessed much better adsorption capability for Pt(IV) than for other metal ions and the maximum saturated adsorption capacity was 222.2 mg g⁻¹ at 308 K, estimated from the Langmuir model. Furthermore, the resin could be regenerated through the desorption of the Pt(IV) anions using the mixture of 1 wt% thiourea and 0.1 M HCl. Finally, the PS-ATD resin could provide a potential application for an efficient process of Pt(IV) recovery from aqueous solutions.