Advanced Spectroscopic Analysis of Glycerin Deoxygenation

This research project addresses the global necessity of transitioning away from a crude oil- based industry toward sustainable and environmentally friendly chemical production. The goal is to upgrade glycerin to fine chemicals. Glycerin is a widely available byproduct generated during the production of sustainable fuels like biodiesel (approximately 1 ton of glycerin is produced for every 10 tons of biodiesel). The focus is on understanding catalytic behavior and the structural evolution of the catalyst. The process of the project to convert this plentiful waste material (glycerin) into valuable fine chemicals, such as diols, alcohols, and propane, which are key intermediates for industrial applications, is called catalytic hydrodeoxygenation (HDO). HDO requires highly efficient catalysts. A catalyst is a substance that speeds up a chemical reaction without being consumed during the process. In this case, the catalysts selectively remove oxygen atoms from the glycerin molecule. In this investigation, bimetallic catalysts (M/Mo/ZrO2, where M represents Nickel, Palladium, or Platinum) are studied. The central innovation of this study is the use of operando spectroscopy, which means analyzing the catalysts dynamically while they are actively performing the reaction, providing real-time insights that traditional methods cannot achieve. To accomplish this, a custom-built, high-pressure continuous flow reactor is utilized, which ensures enhanced control, scalability, and suitability for real-time analysis compared to standard batch reactors. This flow reactor system is then deployed at advanced synchrotron light sources, which are particle accelerators, for experiments. Using powerful X-ray techniques, specifically X-ray Absorption Spectroscopy (XAS) and X-ray Pair Distribution Function analysis (XPDF), the catalysts atomic and electronic structures are captured as it evolves under realistic operating conditions. This allows determining the actual "working state" of the catalyst and identifying crucial structural changes. Furthermore, VUV-PEPICO spectroscopy will be employed to identify short-lived, transient reaction intermediates with high precision. This is crucial for unraveling the exact reaction pathways and mechanisms, enabling fine-tuning the catalyst`s selectivity and performance. By directly linking molecular-level changes in the catalyst structure to its catalytic activity and selectivity, this project aims to provide fundamental insights essential for designing the next generation of highly effective and durable catalysts. The successful outcome will significantly enhance chemical production from sustainable feedstocks, accelerating the transition to a greener society.