The micro-reactor testing of catalysts and fuel delivery apparatuses for diesel autothermal reforming

Abstract

This study investigated two factors affecting the performance of diesel autothermal reforming (ATR): the reforming activity of selected catalysts and the effect of devised fuel delivery apparatuses. When fluorite and perovskite-structured ceramic materials were used as substrates, H-2 yields were higher than when an inert Al2O3 Substrate was used at 700-800 degrees C. Gadolinium (Gd)-doped CeO2 (CGO) had the highest H-2 production rate in the selected substrates. Platinum (Pt) showed better performance than rhodium (Rh) and ruthenium (Ru) when CGO was used as the substrate. Although the nickel (Ni)-added Pt catalyst (Pt-Ni) showed high H-2 yield, carbon deposition over this catalyst was more severe than with Pt. Oxygen ion (O2-) vacancies generated by Gd dopants can enhance the reforming activity of CeO2. When using a microchannel catalyst bed, the performance degradation at high gas flowrates can be compared to a packed catalyst bed of pellet type. For effective fuel delivery, we have introduced an ultrasonic injector (UI) and a plasma injector (PI). The UI-reforming showed greater long-term stability than non-UI reforming because the generation of carbon precursors was suppressed. On the other hand, the PI-reformer had low conversion efficiency, although it had high H-2 selectivity. (C) 2008 Elsevier B.V. All rights reserved.