Interpreting Nonoxidative Ethane Dehydrogenation in an Open Tube Reactor

Several recent studies on the nonoxidative dehydrogenation of ethane to form ethylene have suggested this may be a promising pathway to upgrade products from ethane. The experiments of Riley et al. provide conversion, selectivity, and yield data for ethylene synthesis using bench-scale reactors with three different materials of construction at furnace temperature settings in the range of 575-700 degrees C. Despite being a gas phase reaction, there were significant differences between the quartz, alumina, and stainless-steel reactor tubes. Here, we present an analysis by simulation of the reported experimental results via simplified 1-step kinetic modeling using thermal and flow solvers. The stainless steel and alumina reactor results were fit to one reaction rate, while the quartz tube necessitated a separate mechanism to best fit the experimental results. The quartz tube reactions are faster than the Riley et al. stainless and alumina data as well as the published rate data from other sources. Alumina and stainless tube results, which were fit together, were also significantly faster than those suggested by published rates.