Pt-Cu Catalysts for Catalytic Dehydrogenation of Alkanes for Energy Production

More active, selective and stable catalysts are in demand to increase the yields of olefins production from light alkane dehydrogenation. Cu was reported to promote Pt catalysts and Pt-Cu catalysts has been shown to achieve increased olefin selectivity and decreased deactivation rate. Pt-Cu catalysts with different Pt:Cu molar ratios may have different crystal structure and performance. This study seeks to understand of the promotion effect of Cu on Pt alkane dehydrogenation catalysts. Four different Pt-Cu catalysts with different atomic ratios were prepared and tested for propane dehydrogenation at 550℃. Synchrotron in situ X-ray diffraction and X-ray absorption spectroscopy are used to characterize the structure of the Pt-Cu catalysts. For this series of catalysts, as the Cu loading increases, the selectivity also increases. A 0.66%Pt-2%Cu catalyst has the highest propylene selectivity. Cu was found to form random solid solution and also intermetallic alloy with Pt depending on the catalyst composition.