FUEL 251 |
| High hydrogen yield from fuel processing of hydrocarbon fuels typically requires high conversion from the exothermic, reversible water-gas shift (WGS) reaction. High conversion is attained by increasing water concentration or by lowering operating temperature, thereby creating water balance issues with the former approach or overly large reactors with the latter. An improved method for increasing hydrogen yield is to integrate heat exchange within the WGS reactor to establish a temperature trajectory that enhances local reaction kinetics and reduces the catalyst requirements and therefore reactor size. The potential impact of an improved temperature trajectory is explored for a variety of fuels from steam reforming, autothermal reforming, and wet partial oxidation at various feed compositions. An improved temperature trajectory has been demonstrated in a differential temperature microreactor that was operated with a prototype precious metal catalyst on simulated steam reformate. The reactor designed to reduce CO from 12% dry to less than 1% dry at a power rating of 2 kW electric achieved the desired performance at over 2.5 kW rating. Details of the reactor design and operation are presented. A discussion is also provided on alternative design approaches for small-scale hydrogen production to reduce cost. |
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Fuel Processing for Hydrogen Production: Small-Scale Hydrogen Generation Status and Future Challenges
8:25 AM-12:10 PM, Thursday, August 23, 2007 Boston Park Plaza -- Berkeley Rm, Oral
Division of Fuel Chemistry |