Sustainably modified cordierite/ZrO2 ceramic membranes with <i>Carpobrotus edulis</i> biomaterial for Zn2+ removal from water

Abstract

ABSTRACT The Carpobrotus edulis is used for ceramic membrane modification to create a filter that captures zinc ions (Zn²⁺) from a solution, resulting in a permeate with reduced zinc concentration after filtration. The combination of adsorption with microfiltration can significantly enhance the capabilities of this filtration process. The present study investigates the improvement of ceramic membrane selectivity for Zn2+ ion removal by modifying a cordierite/ZrO2 microfiltration membrane with inert solid biomaterials (ISBM) from dried Carpobrotus edulis plant material. The ISBM microparticles form a superficial layer (1–2 μm thick) on the zirconia surface, creating a dynamic membrane through circulation of a vegetable suspension. The modified membrane (cordierite/ZrO2/ISBM) demonstrated significantly improved performance, achieving a Zn2+ retention rate six times higher than the unmodified ceramic membrane. Retention was stable over time and influenced by initial concentration and pH, with increased retention at higher pH values due to complexation and adsorption. This novel membrane system presents a promising, low-cost solution for effective heavy metal removal in wastewater treatment, leveraging the adsorptive properties of C. edulis and the filtration capabilities of ceramic membranes.