The heat-activated persulfate (heat/PDS) system is increasingly being applied in the treatment of organic polluted water.However, there is still potential improvement in both the mechanism and application of this system.In this study, heat/PDS system was applied to eliminate fluoroquinolone antibiotics (e.g., difloxacin, DIF).Under conditions with 2 mM PDS and 60°C, the efficient degradation of DIF (∼80-100% degradation rate) occurred within the concentration range of 2-20 mg/L.The activation energy was calculated to be 91.25 kJ/mol.Through the ESR, chem. competition, flash photolysis, and barrier energy calculation methods, SO4•- and •OH were confirmed as the main reactive species.DIF•- acted as a mediator, generated from the reaction between O•-2 and DIF, further reacting with PDS to enhance the production of SO4•-.Based on the theor. calculation and mass spectrometry experiment, DIF underwent hydroxylation, ring-opening, and demethylation pathways.Moreover, the heat/PDS system was demonstrated to possess superior adaptability to pH, water matrixes, and ions; trivalent iron and divalent copper significantly promoted the degradation of DIF.This study also proposed a method of using solar concentrated heating, confirming the promising applications for constructing heat/PDS water treatment unit.Ultimately, this research emphasizes the involvement of organic radical mechanisms, intermediate product transformation pathways, and the feasibility of combining solar concentrated heating with PDS technol., providing insights for applying the heat/PDS system to treat DIF in water and wastewater.