ERI: Aqueous Phase Reforming of Multi-Component Carboxylic Acid Systems over Pt Catalysts

Renewable fuel and chemical manufacturing raises significant challenges due to the complex chemistry of biomass sources. Biorefineries show promise for renewably converting biomass to biofuels and chemicals; however, significant inefficiencies are present, as the wastewater streams have high concentrations of dissolved oxygenated hydrocarbons. Aqueous phase reforming (APR) offers a solution by converting these wastewater streams into renewable hydrogen with catalysts. Traditional catalysts display poor APR performance due to strong, nanoscale chemical interactions between different biomass-based chemicals at the interface between the catalyst surface and the wastewater stream. To accelerate the development of high performing APR catalysts, the project will connect experimentally controllable conditions, such as the composition and temperature, to the structure and reactivity of catalytic interfaces. This will be achieved by investigating the nanoscale interactions between a series of biomass-based molecules at a platinum-water interface. Furthermore, the project will enhance science and engineering education by applying virtual reality to enable students to visualize molecular systems at the nanoscale and connect their observations to macroscale chemical properties. Despite APR's potential, studies often overlook the multi-component nature of real biomass-based feedstocks, leading to suboptimal catalyst performance. Leveraging multiscale computational modeling and experimental collaboration, the project will provide insights regarding the interplay between aqueous phase properties and solid-liquid catalytic interfaces. Specifically, the project focuses on characterizing the competitive adsorption and potential energy surface for decomposition of binary carboxylic acid mixtures at a platinum-water interface. Experimentally controllable conditions (i.e., composition and temperature) will be connected to the structure and reactivity of the platinum-water interface via a combination of atomic-scale electronic calculations (i.e. density functional theory) and force field molecular dynamics simulations. Insights gained will inform the design of deactivation-resistant APR catalysts and advance understanding of competitive adsorption and catalytic reactions at complex interfaces. Furthermore, this research aligns with societal goals of biomass utilization and hydrogen economy development, with integrated education and outreach efforts targeting graduate and undergraduate students, including those from underrepresented groups. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.