Growing populations, deteriorating water infrastructure, and climate change are motivating a switch between the traditional centralized water treatment approaches to a more resilient distributed approach. Despite their many attractions, distributed treatment systems are often limited by the transport and storage of chemical reagents. Electrochemical systems may provide a means of addressing this issue because they can be used for in-situ generation of chemicals, pH adjustment, and advanced oxidation processes. Previously, we described an air-diffusion cathode that effectively generated H2O2 and a stainless steel cathode that could convert H2O2 to ●OH with a yield of around 70% at circumneutral pH conditions. In this study, we integrated the two electrodes in series to create a flow-through modular treatment system prototype. To match the H2O2 production kinetics to activation kinetics, the system was optimized in terms of relative electrode areas, applied current densities and flow rates. The treatment prototype was operated under representative solution conditions to assess the effect of natural organic matter and carbonate which act as a ●OH scavengers and produce products that may cause electrode fouling. The metal leaching capacity from the stainless-steel electrode also was monitored. Finally, the energy consumption and approximate cost of the proposed system were compared with other distributed electrochemical water treatment processes.

Electrochemical advanced oxidation for distributed water treatment enabled by air-diffusion and stainless steel electrodes

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.