Sustainable Wastewater Treatment Using Novel Zeolite-Polymer (ZePol) Composite Materials

Abstract

Emergence of effective, durable treatment technology is of paramount importance due to the rising threat of toxic heavy metal pollution of water resources to human health as well as the environment. In order to improve multi-functional adsorption, we present the synthesis and performance of ZePol-4, a novel zeolite-polymer composite made from ETS-4 zeolite, chitosan, polyvinyl alcohol (PVA), and L-cysteine. The crystallinity, porosity, and functional group integrity of the composite were validated by structural and morphological characterizations (XRD, SEM, and EDS). Excellent uptake capacities for important heavy metals were shown by batch adsorption experiments, with equilibrium adsorption capacities of 243.5 mg/g (Pb2+), 170.1 mg/g (Hg2+), 113.5 mg/g (Cu2+), 80.3 mg/g (Cd2+), and 45.3 mg/g (As3+). In accordance with this, ZePol-4 obtained high removal efficiencies in 60 minutes of 98% for Pb2+, 93% for Cd2+, 88% for Hg2+, 75% for As3+, and 70% for Cu2+. The composite required less extensive chemical adjustment because it worked well over a broad pH range, with optimal removal taking place close to neutral pH. The accuracy of the removal data was guaranteed by dual quantification using UV-Vis and ICP-MS. Strong binding interactions and quick kinetics were made possible by the complementary contributions of amino, hydroxyl, and thiol groups through surface complexation and ion exchange. With its quick adsorption, high selectivity, and operational compatibility with actual environmental conditions, ZePol-4 shows great promise as a scalable, environmentally friendly, and highly effective material for tertiary wastewater treatment.