Oxidative steam reforming of light hydrocarbons in a catalytic microchannel reactor

Abstract

Oxidative steam reforming (OSR) reaction of light hydrocarbons (methane and propane) is investigated under exhaust gas reforming (EGR) conditions in a catalytic heat-exchange integrated microchannel by computational and experimental techniques. OSR of propane is investigated by computer-based modeling and simulation studies to demonstrate the e ects of di erent exhaust gas compositions from diesel and gasoline internal combustion engines (ICEs) by parametric variation of the amounts of propane and steam injected into the EGR feed and of the total feed ow rate. Steady-state simulations conducted using computational uid dynamics (CFD) show that e ective heat transfer and uniform temperature distribution can be obtained in the microchannel con guration even at low gas hourly space velocities (GHSVs). Higher H2 and CO yields are possible by injecting more propane and steam into the feed. Increasing total feed ow rate, hence the GHSV improves axial heat distribution, but can lead to reduction in the H2 and CO yields due to insu cient contact time. In the experimental part of the work, micro uidic EGR process is observed via OSR of methane over three di erent Pt- and Rh-based catalyst con gurations. For each catalyst con guration, parametric study of methane OSR is conducted in order to observe the e ects of feed compositions (molar steam-to-carbon (H2O/C) and oxygen-to-carbon (O2/C) ratios) and temperature on methane conversion and on product distribution. The results show that methane conversion is enhanced with the increase in temperature and in the amounts of O2 and H2O in the feed stream. The catalyst combination involving 2wt% Rh/Al2O3 coated catalyst only is found to exhibit the best performance in terms of increased methane conversion, and H2 and CO compositions.