Biocompatible polypyrrole/zeolite composite for chromate removal and detoxification

This study assessed the Cr(VI) removal efficiency, detoxification, and biocompatibility of polypyrrole/zeolite (PPy/Ze) nanocomposite. The composite was prepared by oxidative polymerization of pyrrole with zeolite. Structural study through scanning electron microscope showed that PPy/Ze nanocomposite was circular in shape with size ranging from 30 to 80 nm. The Fourier transform infrared spectra peaks of the composite confirm the presence of zeolite and polypyrrole in the composite. The composite removed 83.5% of Cr(VI) within 50 min and consequently detoxified Cr(VI) through reduction process. Energy dispersive X-ray spectrum supports the adsorption of Cr(VI) onto the composite and X-ray diffraction spectra corresponding to Cr₂O₃ attest Cr(VI) reduction. Cytotoxicity and antimicrobial assay confirmed that the composite was non-toxic and do not retard Listeria monocytogenes and Salmonella typhimurium growth. These results confirm that PPy/Ze composite is an useful and eco-friendly material for Cr(VI) removal and reduction from wastewaters.