Feasibility of UVC-LED/H2O2 advanced oxidation processes as a hybrid water treatment system uniting secondary battery and microbial fuel cell

An innovative hybrid water treatment system consisting of an ultraviolet C light-emitting diode sequentially connected to a secondary battery and microbial fuel cells was developed and systematically optimized via an electrochemical performance test. According to standardized bio-dosimetry, the generated ultraviolet intensity powered by a pre-charged battery was determined to be 2.3x10(-1) mu W cm(-2). The quantified UV intensity was used in calculating the fundamental kinetic parameters for the inactivation of microbial entities and the degradation of organic pollutants during UVC-LED and UVC-LED/H2O2 treatment processes. The fluence-based first-order rate constants were 1.07 and 2.43 cm(2)/mJ for Escherichia coli and 0.10 and 0.18 cm(2)/mJ for MS-2 bacteriophage, respectively. The study detected 2.76-8.00x10(-16) M hydroxyl radicals at steady-state during UVC-LED/H2O2 treatment with 0.3-1 mM H2O2. The second-order rate constant for atrazine during UVC-LED/H2O2 treatment was 1.90x10(9) M-1 s(-1) according to linear regression analysis of atrazine elimination over center dot OH exposure. This comprehensive investigation expands the application of microbial electrochemical systems in water treatment, providing a fundamental kinetic dataset for quantifying and predicting the microbial and (persistent) organic pollutants abatement.