Setshedi, Katlego Z.Kalombo, LonjiNomadolo, NomvuyoHlekelele, LeratoRay, Suprakas SinhaMaity, Arjun2025-02-052025-02-052024-08Setshedi, K.Z., Kalombo, L., Nomadolo, N. et al. 2024, 'Polypyrrole modified granular activated carbon nanocomposite for treatment of wastewater containing highly toxic hexavalent chromium', Macromolecular Materials and Engineering, vol. 309, art. 2300392, pp. 1-14. 10.1002/mame.2023003921438-7492 (print)1439-2054 (online)10.1002/mame.202300392http://hdl.handle.net/2263/100522This study explored the fabrication of Polypyrrole (PPy) and Granular Activated Carbon (GAC) composites (PPy-GAC) for effective removal of toxic hexavalent chromium (Cr(VI)) from aqueous solutions. Two synthesis methods are employed: (1) electrostatic deposition of PPy onto pre-charged GAC paper and (2) in-situ chemical polymerization of pyrrole monomer with GAC particles. Batch adsorption experiments investigated the impact of various operational parameters on Cr(VI) removal. Compared to pristine GAC (54.64 mg g−1), the PPy-GAC composite exhibited a remarkable 3-fold increase in equilibrium adsorption capacity, reaching 175.44 mg g−1. Pseudo-second-order kinetic model (R2 > 0.999) accurately described the adsorption kinetics, while the Langmuir isotherm model (R2 > 0.99) provided a good fit for the equilibrium data. Maximum adsorption capacity (qmax) increased with temperature, reaching 204.08, 243.90, and 270.27 mg g−1 at 298, 308, and 318 K, respectively. Furthermore, a fixed-bed column experiment examined the composite’s effectiveness in continuous Cr(VI) removal, demonstrating its suitability for practical applications. Notably, the PPy-GAC composite successfully removed Cr(VI) from a real wastewater sample containing 68 μg L−1 Cr(VI) obtained from a ferrochrome industry, highlighting its potential for real-world remediation.en© 2024 The Author(s). This is an open access article under the terms of the Creative Commons Attribution License.PolypyrroleAqueous solutionsBatch adsorptionTemperatureSDG-06: Clean water and sanitationArticle