Mechanistic insight into SO4•−/•OH radical for enhancing stability and activity of LaMO3 perovskite toward detoxification of bulk pharmaceutical wastewater: Stoichiometric efficiency and controlled leaching study

•Enhanced PMS utilization efficiency with boosting e−1 transfer in Co+2/Co+3 cycle.•Treatment system LaCoO3/PMS provided very low treatment cost 27.87$/m3 of aqueous solution.•In-situ generated reactive species SO4•– and •OH both play major role on degradation.•Six plausible degradation pathways for ofloxacin were proposed with PMS activation mechanism.•Phytotoxicity of pharmaceutical wastewater on various plant species.