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Pathogenic microbes in water present great risks to environments, water resources, and human health. In the present study, for the first time, a FeCl 3 -activated bermudagrass-derived biochar (FA-BC) was applied to activate persulfate (PS) for E. coli inactivation. The PS activation was ascribed to the presence of Fe 0 and Fe 3 O 4 on the surface of FA-BC, and SO 4 ·- radicals were proved to be the main role for E. coli inactivation using FA-BC activated PS system (FA-BC/PS). Decreasing the pH (5-9) and increasing the PS concentration (50-300 mg/L), reaction temperature (20-50 °C), and FA-BC dosage (100-500 mg/L) resulted in the enhancement of disinfection efficiency of E. coli using FA-BC/PS. 6.21 log reductions of E. coli were achieved within 20 min under the optimal conditions (500 mg/L FA-BC, 200 mg/L PS, pH 7, and 20 °C with 10 7 CFU/mL E. coli in DI water). The FA-BC/PS effectively eliminated various initial concentrations of E. coli (10 5 -10 8 CFU/mL). The E. coli inactivation rate decreased from 0.1426 min -1 to 0.0883, 0.1268 min -1 , and 0.1093 min -1 with the presence of 10 mg/L humic acid, 100 mg/L Cl - , and 100 mg/L HCO 3 - , respectively. In addition, after three cycles of disinfection tests using FA-BC/PS, the E. coli inactivation rate only slightly decreased from 0.1426 to 0.1288 min -1 . The FA-BC/PS also effectively removed the E. coli in real stormwater with a 99.2 % inactivation efficiency within 180 min. The FA-BC/PS in fixed-bed column tests revealed the continuous and high inactivation of E. coli in water. Increasing the FA-BC amount (1.5 %-5 %) and PS concentration (50-200 mg/L) and decreasing the flow rate (2-4 mL/min) caused the lower E. coli concentration in effluent. Therefore, the FA-BC/PS can be considered as a promising and efficient technique for water disinfection., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)