Effects of membrane cleaning on membrane physicochemical properties: Balancing the trade-off between cleaning efficacy and robust membranes

Membrane fouling remains the major operational challenge across several industries, including water, food and bioprocess industries. Various cleaning approaches have been developed to partially restore membrane performance and maximize their long-term application. For instance, chemical cleaning experimental findings revealed restoration of permeability. However, it progressively degrades the polymeric membranes, thus altering structural integrity, mechanical strength, and solute rejection, consequently shortening the membrane lifespan. Therefore, this study reviewed physical, chemical, biological and advanced oxidation processes (AOPs) cleaning strategies and provided evidence on how cleaning agents (acids, bases, oxidants and surfactants) and cleaning conditions (exposure duration, concentrations, temperature, and pH) could alter the physicochemical properties of the membrane. Unlike previous reviews, this study proposes the decision-making framework that balances the trade-off between cleaning, risk of membrane damage and environmental footprint. Furthermore, the study provided standardized cleaning experiments including test metrics, FTIR, tensile, FRR and irreversible resistance analysis. Also, engineered membranes with self-cleaning/healing and chemical-resistance properties are reported. Critical considerations include comparative risk and benefit analysis for industrial-scale adoption. This study presents a framework towards priority research focusing on (i) robust and fouling-resistant membranes, (ii) lifecycle assessment of nanoparticle modified membranes and (iii) industrial adoption of AOP-based cleaning strategies. The review provides a guide for industrial operators and researchers towards increased membrane robustness while protecting the environment.