Selective oxidation over titanosilicate

Titanosilicates molecular sieves, especially TS-1, have been widely studied for the selective oxidation of a variety of organic substrates, using aqueous H202. ° Recently, there have been attempts to substitute aqueous H2O2 by a mixture of H2 and O2 in the presence of metals such as Pd, Pt, Au, etc. Selectivities of 99% for propylene oxide formation from propylene were observed by Haruta and co-workers over Au-containing catalysts. We had also found that the epoxide selectivity in the epoxidation... 

B. S. Uphade, S. Tsubota, T. Hayashi, M. Haruta, Selective oxidation of propylene to propylene oxide or propionaldehyde over Au supported on titanosilicates in the presence of H2 and O2, Chem. Lett. (1998) 1277. 

In general, in case of both phenol hydroxylation and benzene oxidation, the activity increases with increase in Ti-content. This is similar to the earlier reports over titanosilicates [9], The hydroxylation of phenol produces more catechol while phenol selectivity is obtained during benzene oxidation. Ti-impregnated samples were found to be almost... 

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