Monitoring of the catalytic conversion process on single catalyst particles by impedance spectroscopy
Recent studies indicate that heterogeneous catalysts vary tremendously, induced by dynamic changes in the active sites due to gradients in reaction conditions over the catalyst bed, both between and within single particles. Traditional characterization of catalyst particles in large vessels results in measurements representing ensemble averages. On the other hand, individual particle characterization is costly and time consuming and can therefore only be done on a limited amount of particles. There is a need for a single catalyst diagnostic platform for on-line evaluation of the catalytic performance of individual catalyst particles, to increase fundamental understanding of the catalytic conversion process.
One of the routes to assess the behavior of single catalyst particles is by making use of impedance spectroscopy. With impedance spectroscopy, the imaginary and real part of the impedance can be recorded as a function of the frequency of the signal, applied to two conducting electrodes, e.g., manufactured in a microfluidic channel. It is the final aim of this project to come to an optimal catalytic performance via a profound understanding of the catalytic chemical reaction.