NMR Relaxometry as a Tool for Understanding Adsorption in Heterogeneous Catalysis
NMR Relaxometry as a Tool for Understanding Adsorption in Heterogeneous Catalysis
Speaker: J. Ward-Williams, University of Cambridge, UK
The adsorption of liquids on solid surfaces can have serious implications on reaction efficiency in heterogeneous catalysis. NMR relaxometry is one of the few techniques that can provide detailed information on this adsorption process, and is therefore a powerful tool for the rational design and optimization of heterogeneous catalytic processes. In this presentation the theory of high field NMR relaxometry techniques, and their application to catalytic systems will be discussed. In cases where the interpretation of high field NMR relaxometry is ambiguous, fast field cycling (FFC) NMR is shown to be an excellent complementary technique. A case study of different liquids imbibed within γ-alumina is used to demonstrate the sensitivity of FFC NMR to the adsorption process, and to show how FFC NMR can provide a detailed insight into the adsorption and the liquid structuring occurring within the pore space.