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• A novel synergistic technology coupling ultrasound and CNTs/PM (UCP) was developed. • Electron-rich organics could be rapidly removed in the UCP process from raw water. • RMnS oxidation and electron transfer were the main processes for CIP removal. • Ultrasound and CNTs played a critical role in promoting the generation of free RMnS. • CNTs could maintain satisfactory efficiency after repeated use in the UCP process. Recently, free reactive manganese species (RMnS) generated via permanganate catalytic oxidation technology has been applied to contaminants abatement and sludge dewatering. This study proposed a novel free RMnS generation method in ultrasound enhanced carbon nanotube (CNTs)/permanganate process (UCP) for organics removal. Taking ciprofloxacin as a target contaminant, the removal efficiency in the UCP process (9.78 s−1) was remarkably higher than that of the permanganate (0.71 s−1) and CNTs/permanganate (2.57 s−1) processes. CNTs could enrich manganese compounds and ciprofloxacin, and act as an electronic platform for the electronic transfer from ciprofloxacin to manganese compounds for free RMnS generation, which was revealed by DFT calculation and spectrum analysis. Meanwhile, ultrasound further regulated the generation of RMnS as it could transform the inactive solid Mn(IV) into free RMnS. In the UCP process, non-free radical modes including RMnS oxidation (49.8%) and electron transfer (23.5%) were the dominant processes for ciprofloxacin removal in the UCP process, and hydroxyl radical oxidation (13.2%), CNTs adsorption (5.5%), and PM oxidation (8.0%) also contributed to ciprofloxacin removal. Interestingly, CNTs could be well reused in the UCP process as more than 88.75% of ciprofloxacin was removed after five times reuse of CNTs. The UCP process provides a novel strategy for rapid contaminants removal in water treatment via continuous generation of free RMnS. [Display omitted] [ABSTRACT FROM AUTHOR]

• Electrolysis, permanganate, and O3 showed a satisfactory synergistic effect for various organics degradation. • Reactive manganese species (RMnS) and · OH were the dominant reactive species in E-PM-O3 process. • 1 mg L − 1 gaseous ozone dramatically promoted generating both RMnS and · OH with even lower energy consumption. • In situ formed MnO2 played a critical role for generating both RMnS and · OH. • · OH generated by O3 catalysis transfer colloid MnO2 to free mn (Ⅴ) and mn (Ⅵ) in the E-PM-O3 process. A novel water treatment process combining electrolysis, permanganate and ozone was tested in the laboratory. The combination showed synergistic effects in degrading various organic contaminants (like diclofenac, sulfamethoxazole, carbamazepine, etc.). A small amount of O 3 (1 mg L −1, 60 mL min−1) significantly improved the oxidation and mineralization ability of an electro-permanganate process by generating more reactive manganese species and hydroxyl radicals. The combination required less energy consumption than comparable processes. Mechanism experiments showed that the · OH involved was mainly generated by cathode reduction, homogeneous manganese catalysis, and heterogeneous manganese catalysis of O 3 decomposition. Reactive Mn species were generated by electro-reduction, · OH oxidation or/and O 3 activation. In situ generated Mn (Ⅳ) s plays a vital role in generating · OH and reactive Mn species. · OH generated by O 3 catalysis could transfer colloid Mn (Ⅳ) s to free Mn (Ⅴ) aq and Mn (Ⅵ) aq. And both the · OH and RMnS played the dominant role for DCF removal. Increasing permanganate dosage, O 3 concentration, the current density, C l − , or humic acid, and decreasing the pH all enhanced the degradation of diclofenac, but the presence of PO 4 3 − or HCO 3 − inhibited it. Supplementing electrolysis with permanganate and O 3 might be a practical, sustainable, and economical technology for treating refractory organics in natural waters. Image, graphical abstract [ABSTRACT FROM AUTHOR]