Evaluation of polymer inclusion membranes based on PVC containing HDEHP as a carrier for aqueous tetracycline transportation

Abstract

The polymer inclusion membranes (PIMs) are an economical alternative to the several advanced wastewater treatments previously employed for tetracycline (TC) remediation. This study investigates the potential of PIM consisting of an anionic-charged Bis (2-ethylhexyl) phosphate (HDEHP) carrier embedded in polyvinyl chloride (PVC) for aqueous TC microcontaminant remediation. FT-IR, SEM, porometry, water uptake, and contact angle PIM's properties were evaluated. The optimum HDEHP-PIM proved to be physically and chemically stable after prolonged transportation experiments with a mass loss ranging from 0.46 ± 0.02 to 10.13 ± 0.50 %. The extraction and transportation efficiency obtained at a low TC concentration of 5 mg/L was 79 and 77 % using the optimum PIM containing 50 % HDEHP carrier and at optimum conditions. The study shows that self-plasticised PVC polymer embedded with HDEHP carrier satisfactorily transports low residue TC better than the previously reported self-plasticised PVC-Aliquat 336 carrier. Furthermore, the HDEHP-PIM was highly selective and more stable in an acidic than in an alkaline media. The study also shows that increasing the stirring speed enhances the transportation efficiency and duration with an accumulation factor of 11.17 ± 1.04 and 7.86 ± 5.61 % at 500 and 700 rpm, respectively. Hence, significant transportation of low TC concentration using cost-effective self-plasticised HDEHP-PIM is feasible. However, further investigation is required for improved performance, reduced transportation duration, and stability studies based on PIM reusability.