Ozone water production using a SPE electrolyzer equipped with boron doped diamond electrodes

Abstract

Electrochemical ozone production (EOP) is an attractive technology for disinfection and sterilization purposes. This work reports a study on the EOP performance of the solid polymer electrolyte (SPE) electrolyzer, including the optimization of electrode configuration and operation conditions. It is proven that the EOP performance is highly affected by electrode configuration. Tests using BDDs with different B/C ratios demonstrate that BDD-4.9 provides more reaction sites and faster electron transfer rate, exhibiting a high electrocatalytic activity for EOP. Regarding electrode thickness, 0.54 mm in thickness is the most suitable for the EOP from the perspective of less power consumption. Moreover, operation conditions were evaluated. It was found that increasing water flow rate is an effective strategy for promoting ozone dissolution, and within the present experimental range, the water flow rate of 63 L·h−1 was identified. Meanwhile, through the study of all processes occurring inside the electrolyzer at higher current densities, the optimum current density was determined to be 125 mA·cm−2. Based on these results, ozone water presents excellent performance in the killing of Escherichia coli with high inoculum concentrations, indicating potential application performance in the field of environment. HIGHLIGHTS Ozone production by electrochemical technology.; The SPE electrolyzer with specially designed clamping system served as the ozone reactor.; Using a boron-doped diamond (BDD) as the electrode material.; The SPE electrolyzer can continuously and effectively produce ozone by a flow-through system with low energy consumption.; Ozone water shows a considerable bactericidal effect on different concentrations of E. coli.;

Keywords

• bactericidal capability
• boron-doped diamond
• membrane electrode assembly
• ozone water
• solid polymer electrolyte