JB EPSRC NIA Nov18

Optimal Addition Profiles to Control Reactivity and Selectivity of Catalytic Reactions

The final outcome of a chemical reaction depends on several parameters such as the temperature, the solvent and the concentration of reactants and catalyst. These parameters are routinely screened by modifying the initial reaction conditions to obtain the best outcome of the reaction. However, some of these parameters, for example the concentration of reactants and active catalyst, change during the course of the reaction. Thus, the optimal values for these concentrations also change during the course of the reaction. We can correct the concentration of reactants and catalysts by adding them continuously during the reaction. Unfortunately, finding the optimal rate of addition for each time of the reaction is much more complicated than finding the optimal concentration at the beginning of the reaction.

This project will elucidate the best rate of addition of reagents for three different kinds of crucially important catalytic reactions. We plan to do this by applying different strategies, which then may be ultimately applied to other reactions. Some of these strategies will use the knowledge derived from mechanistic studies to identify the concentrations that most affect the final result of the reaction and their optimal values. When possible, we will use the information of modern in situ reaction monitoring tools to instantaneously modulate the rate of addition, which will allow us to find the best rate of addition very quickly. For more challenging reactions, we have proposed a more conservative approach that analyses the behaviour of the reaction by sections. This approximation is more laborious and requires a larger number of experiments, but it can be generally applied to any reaction regardless of its intrinsic complications.

The final stage of study for each reaction aims to analyse the possibility of using the best addition profiles on large scale reactions. To do this, we will test how robust are the optimal addition profiles to the variation of different parameters such as the accuracy in the rate of the addition, the scale of the reaction or the stirring rate.

Ultimately, this project will convert cutting-edge catalytic processes developed in academia, which are unfit for industrial purposes, to useful processes for the manufacture of products such as pharmaceuticals and advanced materials.