Sulfur-doped biochar (SBC) was prepared for the efficient removal of tetracycline (TC) and TC-resistant bacteria via the dual functions of adsorption and peroxydisulfate (PDS) activation. One of the prepared SBC/PDS systems was found to remove 93.89 % of TC with 3.11 times the removal efficiency of the system without sulfur doping (i.e., BC/PDS). The SBC/PDS system inactivated approximately 105 CFU/mL of the TC-resistant bacterium Escherichia coli within 90 min, corresponding to 1.14 times the inactivation efficiency of the BC/PDS system. The introduction of sulfur improved the adsorption rate by 3.09 times, likely due to pore filling and hydrogen bonding. The PDS activation of the SBC/PDS system primarily removed TC and E. coli through nonradical oxidation dominated by 1O2 generation, and the main active sites were vacancy defects. TC adsorption may be the key step for determining the reaction rate of nonradical oxidation. A high correlation (R2 = 0.98) was observed between the adsorption capacity and degradation rate constant of different activator systems, which indicated a synergistic effect between the adsorption and oxidation of TC. This study provides a theoretical basis for the development of advanced oxidation processes utilizing bifunctional materials with a nonradical oxidation pathway for the removal of antibiotics and antibiotic-resistant bacteria.
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