Recent advances in surface modification using polydopamine for the development of photocatalytic membranes for oily wastewater treatment

The contamination of water sources by oily compounds is a severe environmental problem gaining ground in scientific research in recent years since these compounds are generally emulsified in the medium, making their separation difficult. Using photocatalytic membranes has shown interesting results in treating wastewater containing oily compounds, and research has advanced significantly in developing such membranes. The present work seeks to gather an overview of recent research on developing photocatalytic membranes to treat oil-contaminated water, focusing on membrane preparation from surface modification using polydopamine (PDA). This bio-inspired polymer has strong adhesive properties that have been explored for membrane modification, including the adhesion of catalysts. The combination of the photocatalytic function with the separation property of membrane processes optimizes the treatment of this kind of wastewater. However, developing a simple and viable method for large-scale production of these membranes and its application in industrial wastewater treatment is still challenging. Thus, this review critically discusses the latest related publications on the polydopamine-assisted obtention of photocatalytic membranes used for the separation/degradation processes of oily compounds in aqueous media, presenting the challenges of applying these types of membranes in oily wastewater treatment.