Construction of a Zero-gap Flow-Through Microfluidic Reactor with Porous RuO-IrO@Pt Anode for Electrocatalytic Oxidation of Antibiotics in Water.

In this study, a zero-gap flow-through microfluidic reactor was constructed for the degradation of tetracycline and norfloxacin in water using a porous Ti/RuO-IrO@Pt electrode as the anode and porous titanium plate as the cathode. The operation parameters included electrolyte type, electrolyte concentration, current density, initial concentration of pollutants and pH, were investigated. The degradation efficiency and energy consumption were calculated and compared with traditional electrolyzer. In the zero-gap flow-through microfluidic reactor, 100 % of both tetracycline and norfloxacin can be decomposed in 15 min, and high mineralization rate were achieved under the optimized reaction condition. And the reaction was consistent with pseudo-first-order kinetics with k value of 0.492 cm and 1.010 cm, for tetracycline and norfloxacin, respectively. In addition, the energy consumption was 28.33 kWh ⋅ kg TC and 8.36 kWh ⋅ kg NOR, for tetracycline and norfloxacin, respectively, which was much lower than that of traditional electrolyzer. The LC-MS results showed that tetracycline underwent a series of demethylation, dehydration and deamination reactions, and the norfloxacin went through ring opening reaction, decarboxylation and hydroxylation reaction, and finally both produced CO and HO.