AbstractsChemistry

The Deoxygenation and Hydrogenation Properties of Noble Metal-Based Bimetallic Phosphide Catalysts

by Paul M Cochran




Institution: Western Washington University
Department:
Year: 2016
Keywords: Ruthenium catalysts; Phosphides – Properties; Phosphides – Deoxidizing; Hydrogenation; Biomass energy; Metal catalysts; Chemistry; Academic theses
Posted: 02/05/2017
Record ID: 2128334
Full text PDF: http://cedar.wwu.edu/wwuet/519


Abstract

With increasing concern regarding the environmental impacts of fossil fuels, and the difficulty of extracting petroleum feedstocks, alternative liquid fuels are becoming more desirable. Bio-oil, which is oil derived from biomass, is a renewable source of liquid fuels. However, the high oxygen and water content of bio-oil results in high corrosivity and low energy density, making it unusable in the current liquid fuel infrastructure. The process of removing heteroatom impurities from oil is known as hydrotreating. Current hydrotreating catalysts are optimized for refinement of petroleum, and are not suitable for bio-oil deoxygenation. Transition metal phosphides (such as Ru2P) are a class of materials that have garnered interest recently for their unique electronic, magnetic, and catalytic properties. Several metal-rich phosphide phases have also demonstrated promising hydrotreating activity and resistance to deactivation compared to noble metal catalysts. Some bimetallic phosphide phases have been shown to possess even greater activity than their monometallic counterparts due to synergistic effects between the constituent metals. A series of CoxRu2-xP (0 ≤ X ≤ 2) and CoxRh2-xP (0 ≤ X ≤ 2) catalysts supported on silica (SiO2) were prepared via impregnation followed by temperature programmed reduction (TPR). The furan and crotonaldehyde deoxygenation properties of the CoxRu2-xP/SiO2 catalysts were investigated and it was observed that the Co-rich catalysts possessed a higher activity than the Ru-rich catalysts with selectivity towards decarbonylation pathways and the production of C3 hydrocarbons. The CoxRu2-xP/SiO2 series showed no deactivation over 48 h in an 8 mol% furan/H2 feed at 578 K. The crotonaldehyde deoxygenation properties of the CoxRh2-xP/SiO2 were also investigated, and found to be more active than the CoxRu2-xP/SiO2 catalysts, with the Rh-rich catalysts possessing greater crotonaldehyde conversions than the Co-rich catalysts. Advisors/Committee Members: Bussell, Mark E., O'Neil, Gregory W., Berger, Robert F..