Autothermal catalytic reforming with integrated internal heat exchange and enhanced oxygen feed: Design and construction of a device to convert gasoline into hydrogen for use in fuel cell automobiles

A design is presented for an autothermal catalytic reformer for gasoline that incorporates integral internal heat exchange and oxygen enrichment of the feed gas to improve performance. Internal integral heat exchange is intended to transfer heat from the exothermic partial oxidation zone of the reformer to the endothermic steam reforming zone without the use of dedicated heat exchange equipment. Oxygen enrichment of air up to 70% by volume is shown to increase the total hydrogen concentration in the product gas by over 70% relative to using normal air in the feed. Oxygen enhancement also reduces the O2:fuel ratio required to achieve thermoneutrality during a steady-state reaction by approximately 10% on a per mole of fuel basis. The reformer was built to provide approximately 7 kW equivalent of hydrogen. The main determinant of reformer proportions was catalyst pellet size. A system to test the performance of the reformer was also designed. This system was capable of precisely metering iso-octane, water, and oxygen-enriched air to the reformer. The temperature profile in the reformer could be monitored by an array of thermocouples. Product gas flow rate was monitored by a mass flowmeter and product gas composition was determined using a gas chromatograph. The data collected can be used to measure the conversion of iso-octane to hydrogen in the autothermal reformer for a given feed rate of iso-octane, which is a measure of reactor performance.