SusChEM: Promotion of Nickel Catalysts for the Conversion of Biomass-derived Oils to Fuel-like Hydrocarbons

Catalytic decarboxylation/decarbonylation (deCOx) has been proposed as an alternative to hydrotreating for the conversion of lipids and bio-oils to renewable drop-in hydrocarbon fuels. Indeed, deCOx is not only more energy and hydrogen efficient, but it proceeds over benign metal catalysts, not requiring the sulfided catalysts used in hydrotreating. The authors of this proposal have shown that the performance of catalysts comprising earth-abundant and inexpensive Ni can rival that of the rare and expensive precious metals (Pd and Pt) commonly used to catalyze deCOx. Moreover, preliminary results have shown that promotion of Ni catalysts with small amounts of Cu or Sn leads to further enhancements in the efficiency of the process. However, the underlying principles of the catalytic phenomena at play are not thoroughly understood. A more complete understanding of these promotion effects should allow further improvements to the system under study and contribute valuable fundamental knowledge to the catalysis field as a whole. Given that the scope, approach and focus of the proposed work are aligned with those of the Catalysis & Biocatalysis program – this overlap extending to include the emphasis placed on sustainability by the SusChEM initiative – we consider this project to be an excellent fit for this solicitation. Intellectual Merit: The proposed research will enable the authors to parlay the considerable amount of hardware and expertise they have acquired through their work on the catalytic conversion of biomass-derived oils to liquid transportation fuels to accomplish 4 main objectives: 1) to improve the selectivity of Ni catalysts towards fuel-like hydrocarbons by fine-tuning the activity of the catalytically active phase; 2) to improve the resistance to deactivation shown by these catalysts by modifying the active phase electronically and/or morphologically; 3) to establish fundamental structure-activity relationships to rationalize the effect that these changes have on the active phase; and 4) to use mechanistic and kinetic studies to elucidate the reaction mechanism and kinetic parameters for representative feed-catalyst combinations. Since preliminary results indicate that the first two objectives can be achieved through the use of metal promoters, the last two objectives will yield fundamental knowledge concerning the mechanism through which some metals can promote the performance of Ni catalysts in the conversion of lipids to fuel-like hydrocarbons. This constitutes basic knowledge of great importance to the advancement of catalytic science, as the fundamental principles behind promotion phenomena are only partially understood in spite of the fact that metal promoters are widely used in the field of catalysis. Notably, the acquisition of this fundamental understanding will also entail the “development and characterization of low cost, sustainable and scalable-manufactured materials with improved properties”, another topic of interest of the SusChEM initiative. Broader Impacts: This work will provide students with hands-on experience in the field of catalysis for biofuels, thus helping to satisfy the growing demand for the highly skilled scientists and engineers in the renewable energy sector. Notably, the co-PI and the graduate student that will participate in proposed work are Hispanic and Appalachian, respectively, and efforts will be made to recruit an undergraduate student from a historically black college. Therefore, this work will also contribute towards broadening the participation of underrepresented groups in the sciences. However, the authors of this proposal are affiliated with an institution whose outreach program goes beyond student training to include efforts of community engagement and outreach to society at large. Indeed, typical outreach initiatives have been expanded to include a number of novel approaches designed to engage the community and the general public – particularly targeting younger audiences – mainly via the diffusion of scientific data through channels designed to transcend traditional methods. The proposed work will be incorporated into these novel