Iso-Potential Operando Microwave Cavity Perturbation–Spatial Conductivity Changes of a Cu/ZnO/Al ₂ O ₃ Catalyst Inside a Fixed-Bed Reactor During Reverse Watergas Shift Reaction

High Resolution Image Download MS PowerPoint Slide This work explores the combination of Microwave Cavity Perturbation (MCP) with the concept of Iso-Potential Operando Spectroscopy (IPOS) to develop IPO-MCP for measuring conductivity changes in a catalyst within a catalytic fixed-bed reactor (FBR). As proof-of-concept, spatially resolved dielectric properties, species, and temperature profiles were recorded during the reverse water–gas shift (rWGS) reaction on a commercial copper–zinc-alumina (CZA) catalyst. These results reveal a linear electronic structure–activity relationship along the catalyst packing demonstrating that hydrogen significantly enhances the Q-value compared to carbon dioxide in line with previous investigations. This research motivates further application of IPO-MCP to other catalytic systems with distinct conductivity changes.