Enhanced antibiotic wastewater degradation by intimately coupled B-Bi3O4Cl photocatalysis and biodegradation reactor: Elucidating degradation principle systematically

Intimately coupled photocatalysis and biodegradation (ICPB) is an emerging technology that has potential applications in the degradation of bio-recalcitrant pollutants. However, the interaction principles between photocatalysts and biofilms in ICPB have not been well developed. This article covers a cooperative degradation scheme coupling photocatalysis and biodegradation for efficient degradation and mineralization of ciprofloxacin (CIP) using ICPB with B-doped Bi3O4Cl as the photocatalyst. In consequence, a removal rate of similar to 95 % is reached after 40 d. The biofilms inside the ICPB carriers can mineralize the photocatalytic products, thus improving the removal rate of total organic carbon (TOC) by more than 20 %. Interior biofilms are not destroyed by CIP or photocatalysis, and they adapt to ICPB of CIP by enriching in Pseudoxanthomonas, Ferruginibacter, Clostridium, Stenotrophomonas and Comamonas and reconstructing their microbial communities using energy produced by the light-excited photoelectrons. Furthermore, this research gives new opinion into the degradation principles of the ICPB system.

Automated summary

Intimately coupled photocatalysis and biodegradation (ICPB) is a promising technology for efficient degradation of bio-recalcitrant pollutants. This article presents a cooperative degradation scheme using B-doped Bi3O4Cl as the photocatalyst for the degradation and mineralization of ciprofloxacin (CIP) in ICPB. The results show a high removal rate of around 95% after 40 days, with the biofilms inside the ICPB carriers playing a critical role in mineralizing the photocatalytic products and improving the removal rate of total organic carbon (TOC) by over 20%. The study also reveals the resilience of the biofilms to CIP and photocatalysis, and their ability to adapt and reconstruct microbial communities using energy from light-excited photoelectrons.