Non-Thermal Plasma Activation of Gold-based Catalysts for Low Temperature Water Gas Shift
Journal: Angewandte Chemie
Publication Date: 12 April, 2017
Department of: Chemical Engineering and Analytical Science
Disentangling the limitations of clean hydrogen production
The hydrogen economy has been proposed as an alternative to providing energy from traditional fossil fuel technologies. Hydrogen is produced predominantly via a steam reforming process whereby carbon based feedstocks, including renewable sources, are reacted with water at high temperature to form hydrogen and carbon monoxide. The latter is problematic as the main use of the hydrogen within the hydrogen economy is in hydrogen-powered fuel cells and within which the carbon monoxide acts as a poison. In order to purify the hydrogen stream, the water gas shift reaction is undertaken which further reacts the carbon monoxide with water to form hydrogen and carbon dioxide. This reaction is equilibrium-limited and is promoted by low temperature operation whereas the activity of the catalyst increases with increasing temperature.
Researchers at the University of Manchester together with colleagues in Belfast, Aberdeen, Cadiz and Liverpool as part of the UK Catalysis Hub have examined the activation of the gas phase molecules prior to them interacting with the catalyst surface using a non-thermal plasma. They have demonstrated excellent low temperature activity for the water gas shift reaction by using electrical energy to activate the gas phase water and, therefore, reduce the activation barrier for the reaction. This method of activation has the potential to be used for a wide range of applications where low temperature operation is desirable, for example for cold start emission control in cars as well as the water gas shift process for the production of clean hydrogen.