Real-time analysis of catalytic reactions

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Catalysts increase the rate of chemical reactions, but are not themselves consumed in the process. They work by providing an alternative pathway for reaction through an increased number of steps, all of which are faster than the uncatalyzed reaction and that ultimately regenerate the catalyst again. A huge proportion of industrially important reactions at all scales use catalysts. They frequently enable transformations that would otherwise be impossible, they make reactions cleaner and faster, and they generate significantly less waste (their "atom economy", or proportion of atoms in starting materials that end up in products, is often very high). Modern catalysts are often extraordinarily effective, with tiny quantities generating enormous amounts of product. While this efficiency is unquestionably a good thing, it also creates a problem - how do we study catalytic reactions under relevant conditions when only a tiny amount of the mixture is interesting? We have developed novel methods to study catalytic reactions using a technique that was principally the purview of scientists studying large biomolecules such as proteins: electrospray ionization mass spectrometry (ESI-MS). We have used it in conjunction with other real-time techniques to study the dynamics of reactions across 5 orders of magnitude differences in concentration. Now, we'll use robotics to help us pair ESI-MS with traditional off-line methods, and deploy our new ion mobility mass spectrometer to characterize ions by both shape and composition in real time. Our new triple-quadrupole instrument, typically used by chemists in ultra-trace analyses, will be targeted at short-lived intermediates for which other methods have not been able to detect for lack of sensitivity. The vast amounts of data we will gather will need modern tools for interpretation, and we plan to write and deploy algorithms that will identify dynamic behavior characteristic of the most interesting components of an evolving reaction and flag them for human inspection. We will utilize modern tools for processing big data and will develop methodologies as required for our unique applications. In doing so, we will obtain unprecedented insight into the way in which reactions proceed. We will use our understanding to rationally improve catalysts and to develop cleaner, faster and more efficient ways of adding value to chemicals into higher value materials. The results will have impact on chemists who make polymers, fuels, pharmaceuticals, agrochemicals, commodity chemicals: any synthetic process relying on catalysis that still has room for improvement stands to benefit from a more detailed understanding of that process.