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Concerning carbon monoxide, hydrogen sulfide and ammonia, which are likely to be present in hydrogen fuel as impurities, a study was conducted to evaluate the impact of these impurities on the performance of proton exchange membrane fuel cells (“PEMFC”). The study involved a fuel cell performance test using a single cell and the analysis of exhaust gases from the cell. The fuel cell was operated continuously for 10 hours under acceleration test conditions at a 1,000 mA/cm2 current density and a 17 % fuel gas utilization. The results: the cell performance declined when any of the three impurities was present at lower than ppm content levels (0.2 - 0.5 ppm) in hydrogen fuel. Pt-Ru alloy catalysts, known for their higher resistance than Pt to poisoning by carbon monoxide, failed to show improvement of resistance to poisoning by hydrogen sulfide and ammonia.

Intermittent Dual-fluid Exhaust Burner (IDEB) has been developed to reduce emissions from methanol fueled vehicles during the warm-up period after a cold start. The IDEB does not need any special fuel injector or blower, and has been built mainly through software modification of an ECU. An FTP mode test while operating an IDEB confirmed that the catalyst temperature was rapidly increased to significantly reduce the emissions to meet a level of ULEV standards.

This study describes the ignition of methanol spray formed by an ultrasonic atomizer under sub-zero conditions and the design of the methanol combustor as a H2+CO generator, based on partial oxidation reaction, for cold starting methanol engines. The methanol spray formed by the ultrasonic atomizer was observed to be ignited using a conventional ignition system even at sub-zero temperatures. Analysis of the spray characteristics showed that this successful ignition was attributed to the high amount of methanol vapor generated, which results from the fine spray and low momentum. The combustor using the ultrasonic atomizer was designed and tested. The combustor produced gaseous starting fuel (H2+CO) satisfactorily by using an adequate air register.