Paper HC-ThP1
The Role of Boron in Supported Platinum Dry Reforming Catalysts

Thursday, October 24, 2019, 6:30 pm, Room Union Station B

Dry reforming of methane (DRM) has been proposed as an alternative to coal or natural gas production of synthesis gas, and the process has been optimized with various metal catalysts to enhance catalytic activity and reduce surface carbon contamination. In this work, boron was paired with platinum, a highly active DRM catalyst, on a silica support material, and surface characterization techniques were used to determine how the presence of boron affected the metal catalyst and the catalytic performance. X-ray photoelectron spectroscopy (XPS) revealed the existence of trigonal (BO₃ structures) and tetrahedral (BO₄ structures) B-containing surface species, which agreed with solid-state ¹¹B NMR results. Density functional theory (DFT) calculations were performed to determine the thermodynamically stable configuration of the B/SiO₂ species, as well as the most favorable species for platinum adsorption. Tetrahedrally coordinated boron was found to be the most favorable species for platinum adsorption. A butane dehydrogenation reaction was utilized to produce fully deactivated Pt/B/SiO₂ catalysts samples for further analysis. After complete catalyst deactivation, ¹¹B NMR combined with theoretically-predicted isotropic chemical shifts calculated by Amsterdam Density Functional (ADF) revealed that, in addition to BO₃ and BO₄ fragments, a boron-carbon surface species had been formed during butane dehydrogenation, but this was only observed on catalysts containing platinum. From this observation, it has been concluded that platinum causes carbon contamination during this reaction, but it is mitigated by the presence of boron.