Coupled microalgal biofilm production and photocatalytic removal of chlorophenol using optical fibers

Phenolic pollution from wastewater induces harmful effects on aquatic ecosystems and human health, calling for advanced remediation methods. Common methods have a single purpose, e.g., contaminant degradation, whereas there is few knowledge on methods combining degradation and algal production. We coupled N-doped TiO 2 -coated photocatalysis with optical fibers and a microalgal biofilm to both remove 4-chlorophenol and produce biomass. We also monitored bacterial population and biomass production in microalgal biofilms. Results show that the biofilm maintained rapid removal of 4-chlorophenol while maintaining the growth of the microalgal biomass, with values of about 78 µM/h for 4-chlorophenol removal, 41 µM/h for dechlorination and 1.8 g/h/m 2 for the rate of biofilm growth. The biofilm became enriched in Salinarimonas and Pseudomonas. Our findings thus reveal a synergy between an optical catalyst and a bioreactor for potential wastewater remediation and microalgal biomass production.