Reducing emissions in fuel combustion and oxygen production with chemical looping.
Chemical looping describes cycling processes where a material is employed as oxygen carrier in successive oxidation-reduction (Redox) reactions. This process has application in thermal energy storage, oxygen production, carbon capture and gasification.
Dr Mehdi Jafarian is currently developing a new generation of chemical looping processes, in which a liquid metal oxide is employed as oxygen carrier – this will make the process more efficient than existing chemical looping technologies.
CET is looking at adapting this technology to reduce emissions in fuel combustion and oxygen production. CET is also developing new processes for efficient solar thermal energy storage using chemical looping technology.
How chemical looping works
Firstly, the oxygen carrier is reduced because of a difference in chemical potential of the oxygen in the carrier phase and the gas phase. This difference can be caused by an external oxidant (e.g. a fuel) or by the lower partial pressure of oxygen in the gas phase compared to equilibrium partial pressure at the associated temperature. To close the loop, the oxygen depleted solid material is re-oxidized in an oxygen-rich environment and the cycle is repeated.