Microplastics (MPs) are pervasive emerging contaminants in freshwater and drinking-water systems, and conventional treatment processes may achieve insufficient removal of smaller MP fractions. Membrane filtration provides an effective barrier to MPs; however, commercial ceramic membranes can be relatively expensive. In this work, low-cost porous ceramic membranes were fabricated by extrusion-based three-dimensional (3D) printing of a kaolin–rice husk paste, followed by sintering at 1200 °C. The removal of model spherical polyethylene (PE) and irregularly shaped polyethylene terephthalate (PET) MPs across different particle-size fractions was evaluated using dead-end filtration and benchmarked against a commercial ceramic membrane. The 3D-printed membrane removed 58.3 ± 3.6% of 1–10 µm PE particles, while complete removal was achieved for the 75–90, 300–355, and 600–710 µm PE fractions. For PET, removal efficiencies of 80.8 ± 0.9%, 94.9 ± 1.8%, and 100% were obtained for the 10–45, 45–75, and 75–150 µm fractions, respectively. By comparison, the commercial membrane achieved 100% removal across all PE and PET fractions tested. The fabricated membrane had a modal pore size of 0.80 µm and an estimated cost of USD 2.98, compared with USD 54.45 for the commercial 0.45 µm membrane. Thus, the 3D-printed membrane effectively removed medium and large MP fractions, while its estimated fabrication cost was approximately 94.5% lower than the purchase cost of the commercial membrane used for comparison. Although its larger pore size resulted in incomplete removal of the smallest MP fractions, the combination of effective removal of larger MPs and substantially lower estimated fabrication cost demonstrates the potential of extrusion-based 3D printing as an alternative approach for producing ceramic membranes for MP removal.

Three-dimensional (3D) printing has emerged as an alternative fabrication approach for membrane development, offering increased flexibility in membrane geometry, architecture, and material integration. Conventional membrane fabrication methods enable large-scale production but suffer from limited tunability of internal architecture, constraints on material combinations, and challenges in reproducibility. In contrast, 3D printing enables precise layer-by-layer construction, customizable pore morphologies, and the incorporation of functional fillers, thereby expanding the design space for high-performance membranes. Polymeric membranes produced by fused deposition modeling, direct ink writing, digital light processing, and electrohydrodynamic techniques have demonstrated enhanced permeability and shape-defined porosity. Hybrid membranes integrating polymers with nanoparticles, ceramics, and catalytic materials exhibit improved mechanical stability, antifouling behavior, and multifunctionality. Ceramic membranes fabricated through 3D printing show advances in structural precision, high-temperature stability, and the integration of catalytic and photocatalytic functionalities for the removal of micropollutants, pharmaceuticals, and oil-in-water emulsions. Despite rapid progress, challenges remain, including the optimization of printing inks and rheology, multi-material co-printing, scale-up, and long-term fouling resistance. This review highlights opportunities for future development, particularly in hybrid catalytic systems, bio-derived raw materials, and digitally designed architectures. Overall, 3D printing represents a rapidly evolving fabrication approach that provides new opportunities for controlling membrane architecture and integrating functional materials for water treatment applications.