Mechanism of a low temperature exhaust aftertreatment catalyst

NOx from combustion exhaust is a contributor to poor air quality, a global issue. Low carbon fuels will also produce NOx emissions. Current catalytic technologies are unable to convert NOx at low exhaust temperatures typical of queue driving or where engineering constraints prevent catalyst placement close to the source.
LowCat is an iron silicate material under development at the University of Leeds. LowCat can catalyse the reduction of NO2 by reaction with NH3 at ambient temperatures. LowCat can also simultaneously reduce NO and oxidise CO at temperatures competitive with industry standard technologies.
In the present phase of development we are optimising the catalyst manufacturing process and investigating the mechanism of activity. We have produced a VASP-DFT model of LowCat and are selecting crystal terminations for simulation of interactions with target gas species.
We will perform inelastic neutron spectroscopy measurements with TOSCA to identify reaction intermediates and provide information on the binding and reactivity of reagents on the catalyst. These results will constrain our computational modelling of the catalyst reactivity and provide a benchmark for a new diffuse reflectance infra-red Fourier transform spectroscopy facility at the University of Leeds.
Taken together with future work, these results will allow simulated performance of the catalyst in different combustion exhaust environments and support targeting of specific markets for commercialisation.