Mechanistic study into the direct epoxidation of propene over gold/titania catalysts

作者：Nijhuis TA^*; Visser T; Weckhuysen BM

来源：Journal of Physical Chemistry B, 2005, 109(41): 19309-19319.

DOI：10.1021/jp053173p

The epoxidation of propene over gold/titania based catalysts was investigated using different techniques. Infrared spectroscopic information showed that one key step in the reaction mechanism is a reaction catalyzed by gold between titania surface groups and propene. In this reaction step, a bidentate propoxy species is formed on titania. This species adsorbs strongly on the catalyst, and it is the same species which is formed when propene oxide adsorbs on titania. Gravimetrical adsorption experiments and catalytic tests show that product adsorption and desorption are important factors determining the catalytic activity and the catalyst stability. By combining the information from different techniques, a kinetic mechanism is proposed.

• 出版日期2005-10-20