Geopolymeric membranes: A comprehensive review of emerging wastewater treatment solutions

Abstract In today's world, wastewater treatment has become a critical challenge for environmental sustainability and public health, particularly due to the increasing presence of toxic metals and non‐biodegradable contaminants. Traditional methods such as adsorption, precipitation, ion exchange, membrane separation, and filtration categorized under chemical, physical, or biological approaches, are often limited by high costs, low efficiency, or negative environmental impacts. The selection of these techniques depends on effluent characteristics, operational conditions, and wastewater volume. Membrane‐based technologies have emerged as promising alternatives, offering higher efficiency, selectivity, and adaptability compared to conventional processes. Among these, geopolymer membranes represent a novel class of inorganic materials, synthesized through an eco‐friendly and versatile geopolymerization process. These membranes are typically fabricated from aluminosilicate precursors sourced from industrial byproducts like fly ash, rice husk ash, and phosphate tailings, thereby promoting waste valorization and sustainability. What distinguishes geopolymer membranes is their excellent thermal stability, robust chemical resistance, and highly tunable pore structure and surface properties. These characteristics enable them to function effectively under harsh conditions and selectively remove a broad spectrum of contaminants, potentially outperforming traditional polymeric and ceramic membranes. Their modular design also allows integration into customized advanced treatment systems tailored to specific pollutants. This review presents a comprehensive overview of the geopolymerization mechanism, key factors influencing membrane performance, and diverse applications in wastewater treatment. Special emphasis is placed on addressing current challenges such as scalability, fouling resistance, and long‐term durability, highlighting how geopolymer membranes can offer innovative solutions for sustainable water management and pollution control.