Recent advances and future perspectives in ceramic-based nanofiltration membranes: Material innovations, applications, and sustainability challenges

The demand for advanced water treatment technologies has increased with the expansion of industrial activities and the tightening of environmental regulations. Nanofiltration (NF) membranes have garnered considerable attention because of their selective separation performance and energy efficiency. The need for ceramic NF membranes has emerged as they provide the high chemical stability and precise selectivity required to remove recalcitrant pollutants, such as low-molecular-weight compounds discharged from the semiconductor and pharmaceutical industries. However, research on ceramic NF membranes remains limited, and reviews that comprehensively examine their technological developments are rare. This review systematically analyzes the studies on ceramic NF membranes published over the past 5 y, focusing on fabrication strategies, structural properties, surface modification, separation performance, and long-term operational stability. Special attention is paid to enhancing selectivity and permeability through pore structure and surface charge control, antifouling strategies, and changes in membrane performance under various operating conditions. Applications in water treatment and resource recovery were evaluated to assess their practical applicability. Lastly, key challenges toward industrial implementation, including the enhancement of manufacturing feasibility, the advancement of antifouling strategies, and the integration of multifunctional properties, have been identified through this review. These insights suggest future research directions for advancing industrial applicability of ceramic NF membranes.