Correlating Oxygen Species with Product Selectivity for Dehydrogenation of Butane over Titanium Mixed Oxide Catalysts

This study investigated the dehydrogenation of butane over TiO2-based catalysts prepared by a co-precipitation method. The catalysts were characterized in detail using various surface techniques, such as XRD, XPS, SEM, and pyridine-FTIR. Their performances toward butane dehydrogenation showed that the product distribution was considerably affected by the reaction temperature and the composition of the catalysts. Two different selectivity regions were observed for most of the catalysts. A higher butene selectivity over butadiene was obtained at relatively low temperatures, while an opposite trend was observed at high temperatures. In situ DRIFT measurements did not find an obvious change in the reaction pathway for butane dehydrogenation over the TiO2-based catalysts. The variation in selectivity with temperature can be well correlated with the different types of oxygen species on the catalysts.