Activation of peroxymonosulfate by La₂CuO₄ perovskite for synergistic removal of Microcystis aeruginosa and microcystin-LR in harmful algal bloom impacted water

The cyanobacterial blooms induced water safety problems have attracted tremendous concerns due to the adverse influences on aqueous ecosystem and human health. This study developed a novel perovskite-type catalyst for heterogeneous peroxymonosulfate (PMS) activation as an emergency measure to remove harmful algae. The results indicated that significant removal efficiency of Microcystis aeruginosa cells (97%) and chlorophyll-a (100%) was achieved within 20 min in La₂CuO₄/PMS system without significant release of dissolved organic carbon and metals in water. ^•OH, SO₄^•-, ¹O₂ and ^•O₂^- generated were all responsible for algae inactivation and subsequent algal organic matters removal. Moreover, the heterogeneous catalytic mechanism was proposed that La portion in La₂CuO₄ favored the cells destabilization by increasing zeta potential of algae suspension, while variable Cu portion facilitated the electron transfer to improve the yields of ^•OH and SO₄^•-. This study demonstrates that the new catalytic PMS process promises viable and effective control of harmful algal bloom impacts in water treatment.