Porous Biopolymer–MOF Composites for Water Treatment: From Material Design to Practical Performance

Porous biopolymer platforms integrated with metal–organic frameworks (MOFs) pair the processability of polymer networks with the high surface area and tunable chemistry of MOFs, but reported performance is often difficult to compare across studies due to inconsistent metrics, idealized batch testing, and limited attention to transport, regeneration, and matrix effects. This review evaluates porous biopolymer–MOF composites from a platform-level perspective, emphasizing how architecture, MOF placement, and operating mode shape performance under realistic constraints rather than isolated adsorption capacities. Performance trends are synthesized across major contaminant classes (heavy metals, dyes, pharmaceuticals, and PFAS), focusing on dominant interaction mechanisms and the penalties imposed by diffusion limitations, fouling, and competitive solutes. Regeneration and durability are treated as central determinants of viability, alongside leaching risk and water-matrix realism. To improve comparability and translation, a minimum reporting framework is proposed, specifying essential parameters for both batch and flow systems. Overall, the review provides a structured basis to judge when porous biopolymer–MOF composites justify added complexity for sustainable water treatment.