UC Berkeley

The increasing demand for propene exceeds the capacity for its production by petroleum cracking and steam reforming of naphtha, creating what is called a “propene gap.” This gap can be filled by the direct dehydrogenation of propane derived from the condensable fraction of natural gas produced by the fracking of shale. Prior research has demonstrated that supported Pt nanoparticles are quite effective for propane dehydrogenation (PDH) but readily poison due to coking. The rate of this process can be reduced by reducing the size of the Pt nanoparticles and alloying Pt with a non-noble metal such as Sn, Zn, Fe, etc. A further loss of activity with time on stream occurs due to particle agglomeration. This process can be impeded by anchoring Pt nanoparticles using a non-noble metal that is incorporated in the support and interacts strongly with Pt. This thesis explores the possibility of introducing Sn into the silanol nests of dealuminated BEA zeolites to produce Sn/DeAlBEA and then dispersing Pt onto this support to produce PtSn/DeAlBEA. Characterization of these materials by XRD, UV-vis spectroscopy, XANES, EXAFS, and IR spectroscopy of adsorbed pyridine, deuterated acetonitrile, and CO was used to develop a detailed understanding of the structures of Sn/DeAlBEA and PtSn/DeAlBEA. This information aided the interpretation of the effects of catalyst composition and structure on the performance of PtSn/DeAlBEA catalysts for PDH.