Polymer electrocatalysts for electrolytic deoxygenation of thermal fluids

Research question

There is about 8 mg/l of dissolved oxygen (DO) in water at atmospheric pressure. This DO is detrimental in many processes and applications as it triggers the oxidation of metals and organic matters. The idea of the electrolyser is to use an electrochemical reaction to consume the dissolved oxygen by its reduction into water. For that reaction to take place, it is necessary to use electrocatalyst typically based on Platinum Group Metals, which are Critical Raw Materials. In this project, we investigate a novel design/concept for the electrolyser to remove dissolved oxygen (DO) from water or thermal fluids. We explore the possibility for π-conducting polymer to be electrocatalysts for ORR at the cathode. In the electrolyser, we also introduce a redox molecule (RAH2) in the thermal fluid that can be oxidized at the anode to avoid its degradation. This reaction compensates for the reduction of oxygen at the cathode.

Sustainability aspects

Beside replacing critical raw materials electrocatalysts by organic conducting polymers that are low-cost, solution processible and made of atomic element of high abundancy, our finding also indirectly impacts one of the major problems of society such as corrosion. For instance, corrosion decreases the performance of heat exchangers in power plants. Today there exists no efficient, high throughput and low-cost method to reach low DO level (~1 µg/l). If such a method could be made available for water based thermal fluids, the corrosion could be slowed down even more, this would lead to an increase of efficiency for energy systems, less maintenance cost and longer material lifetime, improving the sustainability and circularity of major economy flows in our society.