Toluene oxidation on V-Sb oxide. Study of the doping effect

B. IRIGOYEN, S. LARRONDO, N. AMADEO Y A. JUAN

Chicago, EEUU

Congreso; 222nd ACS National Meeting; 2001

Selective oxidation is at present the main method to produce numerous chemical products of commercial interest. Nevertheless, it is an intriguing question what factors prevent a hydrocarbon molecule from undergoing total oxidation. In this sense, catalysts based on V-Sb oxide have been widely studied in the last years applied to (amm)oxidation reactions. It is known that VSbO4 catalyst have the redox couples, V3+/V4+/V5+ and Sb3+/Sb5+, and that its activity and selectivity are affected by these ratios. Moreover, partial substitution of Sb by Ti increases the content of V4+ changing the oxide redox properties. This is related to the benzaldehyde selectivity enhancement obtained in the VSb1-xTixO4 catalyst reaction tests. On the other hand, V1-xSbTixO4 shows low activity and selectivity. Thus, in this work a theoretical study is performed to describe the changes produced by replacing Sb or V sites by Ti on the electronic structure of the catalyst.