Support effects on catalytic performance for selective combustion of hydrogen in the presence of propene

γ-Al2O3, α-Al2O3 and SiO2 have been employed as the supports of Pt catalysts for the process of selective hydrogen combustion (SHC) in the presence of propene at high temperature. High H2 conversion can be obtained over different catalysts being accompanied with a considerable amount of C3H6 consumption. But the oxidation of C3H6 to CO and CO2 keeps under a low level over all catalysts. An A factor has been introduced to evaluate the priority of H2 conversion over C3H6 conversion given by the catalysts. The results show that the Pt catalyst supported on α-Al2O3 with 1.6 wt.% Pt loading can bring about the highest value of A factor among all catalysts. But γ-Al2O3 is not a proper support in terms of A factor. The support effect has been studied on the basis of characterization of physicochemical properties of the supports and the catalysts by means of BET, NH3-TPD, TG, TPR and TEM techniques. The results reveal that the support with lower specific surface area and lower acidity is of help to generating larger Pt particles with less interaction with the support, thus being beneficial to the diminishment of C3H6 consumption. The H2 combustion selectivity can be improved accordingly.

► Supported Pt catalysts were tested for selective combustion of H2 in C3H6 (SHC).
► 1.6 wt.% Pt/α-Al2O3 is superior to the other catalysts for SHC.
► Inert support with small specific surface area is favorable to SHC.
► Small Pt particles on support do harm to the catalytic selectivity.
► Propene combustion accounts for small portion of propene conversion.