The effects of SMSI on m-Cresol hydrodeoxygenation over Pt/Nb2O5 and Pt/TiO2

Abstract The hydrodeoxygenation (HDO) of m-cresol was studied on Pt/Nb2O5/MgAl2O4 and Pt/TiO2/MgAl2O4 catalysts to understand the effects of Strong Metal Support Interactions (SMSI). The Nb2O5 and TiO2 supports were prepared as 0.7-nm films on MgAl2O4 by Atomic Layer Deposition (ALD) to ensure that the structures of the catalyst were the same. When reduced at 773 K to place Pt in the encapsulated state, Pt/Nb2O5/MgAl2O4 was much less active than Pt/MgAl2O4 at 573 K but much more active at 623 K. While Pt/MgAl2O4 deactivated rapidly due to coking, Pt/Nb2O5/MgAl2O4 showed significantly better coke tolerance and was almost 100% selective towards toluene production. Pt/Nb2O5/MgAl2O4 reduced at lower temperatures exhibited intermediate catalytic properties. The effect of reduction temperature on Pt/TiO2/MgAl2O4 was much less and this catalyst was more similar to Pt/MgAl2O4 than its Nb2O5 counterpart. The implications of these results for understanding the nature of oxide promoters on HDO of m-cresol are discussed.