Membrane Technologies at the Frontier: A Review of Advanced Solutions for Microplastics and Emerging Contaminants in Wastewater

Microplastics (MPs) and emerging contaminants (ECs) are increasingly prevalent in environments due to their persistence, toxicity, and resilience against standard wastewater treatment methods. This review presents a comprehensive analysis of contemporary and advanced membrane-based techniques, highlighting their removal efficacy, recovery potential, and fundamental mechanisms such as size exclusion, adsorption, electrostatic interactions, and biodegradation. This review emphasizes the physicochemical properties of MPs, including particle size, shape, polymer type, and hydrophobicity, and their significant impact on membrane performance and fouling behavior. Key findings reveal that membrane fouling is a primary constraint affecting operational efficiency. This study identifies the types of fouling standard, total, intermediate, and cake formation that contribute to flux deterioration and necessitate increased energy expenditures during prolonged operation. Additionally, this research highlights the detrimental effects of mechanical abrasion and scaling on membrane integrity and lifespan. Future prospects for membrane technology are explored, positioning it as a leading solution for sustainable wastewater treatment. Essential directives include the development of intelligent membranes responsive to environmental stimuli, AI-driven monitoring systems, and modular and decentralized treatment units. Moreover, the implementation of circular economy principles is discussed, emphasizing concurrent treatment and resource recovery, such as nutrients, biogas, and clean water. The regulatory and legislative implications of membrane-based treatment are also addressed, underscoring the importance of standardization, performance evaluation, and sustainability. Ultimately, this analysis positions membrane technologies as pivotal instruments in the advancement of intelligent, energy-efficient, and regenerative wastewater management systems.