Rational design of cobalt sulfide anchored on nitrogen-doped carbon derived from cyanobacteria waste enables efficient activation of peroxymonosulfate for organic pollutants oxidation

With the increasing of eutrophication in water body, algae blooms have become one of the global environmental problems. The cyanobacteria waste has placed a severe burden on the environment and transforming cyano-bacteria into functional materials may be a wise approach. Herein, cobaltous sulfide/nitrogen-doped biochar (N-BC/CoSx) composite was synthesized by pyrolysis of cyanobacteria waste. The N-BC/CoSx showed excellent performance in peroxymonosulfate (PMS) activation for enrofloxacin (ENR) degradation, which could remove more than 90% ENR within 60 min. The influencing factors of pH and catalyst dosage on ENR removal efficiency were studied. The N-BC/CoSx showed good recyclability in the cycle runs. The radicals (O2 center dot-, OH andSO4 center dot-) and the non-radical species (charge transfer and 1O2) were generated in the ENR degradation. The cycle of Co(II)/Co(III) m ay contribute to the radical generation process. This work proved that metal sulfide modified cyanobacteria biochar has a specific application value in water pollution control and provides a new method for resource utilization of cyanobacteria.

Automated summary

With the increasing of water eutrophication, algae blooms have become a global environmental problem. This study synthesized a cobaltous sulfide/nitrogen-doped biochar composite from cyanobacteria waste and showed that it had excellent performance in degrading enrofloxacin. The study also investigated the influencing factors of pH and catalyst dosage on the degradation efficiency.