Chemical engineer Evonik reports that it has developed a novel anion exchange membrane process that it hopes will contribute to a cost breakthrough in the electrolytic production of hydrogen.
The production of ‘green’ hydrogen is still much more expensive than conventional hydrogen, which is generally obtained from methane gas in a process that releases carbon dioxide. Along with a supply of sufficient low-cost electricity generated from renewables, investment in the electrolyser is a key factor in cost-efficient production of green hydrogen.
The central component of the electrolyser is an ion-conducting membrane.
“Our membrane could allow the commercial realisation of highly efficient and economically viable electrolysis technology,” says Oliver Conradi, who is responsible for membrane research at Creavis, Evonik’s strategic innovation unit.
The membrane developed by researchers at Creavis comprises a resistant polymer with excellent conductivity. Conradi says: “The polymer chemistry behind this membrane is the key to efficient electrolysis”.
Electrolysis with anion exchange membranes has clear benefits compared with other electrolytic processes such as conventional alkaline electrolysis using diaphragms (AEL) or the more recent method of proton exchange membrane electrolysis (PEM) which is highly dependent on raw materials including precious metals.
The innovative AEM concept reduces investment costs because the cells used for electrolysis in alkaline conditions do not require precious metals, and far less expensive materials can be used. The AEM electrolysis process also exhibits high current density, high efficiency levels, and flexibility.
This development forms part of the EU funded CHANNEL project, a consortium of partners from industry and research organisations that will construct and test an AEM electrolysis system based on the Evonik process. CHANNEL stands for ‘Cost-efficient Hydrogen production unit based on ANionN exchange membrane Electrolysis’. The project will run for three years and receive funding of around €2 million from the European Union’s Horizon 2020 research programme.