Assessing the surface modifications following the mechanochemical preparation of a Ag/Al2O3 selective catalytic reduction catalyst

24Citations
Citations of this article
18Readers
Mendeley users who have this article in their library.

Abstract

The surface modification of a mechanochemically prepared Ag/Al 2O3 catalyst compared with catalysts prepared by standard wet impregnated methods has been probed using two-dimensional T 1-T2 NMR correlations, H2O temperature programmed desorption (TPD) and DRIFTS. The catalysts were examined for the selective catalytic reduction of NOx using n-octane in the presence and absence of H2. Higher activities were observed for the ball milled catalysts irrespective of whether H2 was added. This higher activity is thought to be related to the increased affinity of the catalyst surface towards the hydrocarbon relative to water, following mechanochemical preparation, resulting in higher concentrations of the hydrocarbon and lower concentrations of water at the surface. DRIFTS experiments demonstrated that surface isocyanate was formed significantly quicker and had a higher surface concentration in the case of the ball milled catalyst which has been correlated with the stronger interaction of the n-octane with the surface. This increased interaction may also be the cause of the reduced activation barrier measured for this catalyst compared with the wet impregnated system. The decreased interaction of water with the surface on ball milling is thought to reduce the effect of site blocking whilst still providing a sufficiently high surface concentration of water to enable effective hydrolysis of the isocyanate to form ammonia and, thereafter, N2. © The Royal Society of Chemistry.

Cite

CITATION STYLE

APA

Ralphs, K., D’Agostino, C., Burch, R., Chansai, S., Gladden, L. F., Hardacre, C., … Taylor, S. F. R. (2014). Assessing the surface modifications following the mechanochemical preparation of a Ag/Al2O3 selective catalytic reduction catalyst. Catalysis Science and Technology, 4(2), 531–539. https://doi.org/10.1039/c3cy00945a

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free