| In this thesis ammonia autothermal reforming has been investigated. Experiments involving a variety of catalytic metals, catalyst supports, and reactor configurations have been undertaken in an effort to gain insight into the reforming of ammonia. In order to achieve large ammonia conversions in short periods of time, reactor configurations evolved from simple quartz single-pass straight-tube reactors to complex alumina double-pass coaxial reactors with heat integration capable of operating at temperatures in excess of 1,000°C at gas hourly space velocities in excess of 105 hr-1 . It was determined that the autothermal reforming of ammonia with oxygen over both supported ruthenium and nickel catalysts achieves ammonia conversions and therefore energy densities that yield this process a potential fuel processor for powering a PEM fuel cell. The autothermal reforming of ammonia over these catalysts yields ammonia conversions in excess of 99% for feed gas with an ammonia-to-oxygen ratio up to 4 and conversions in excess of 90% for ammonia-to-oxygen ratios up to 6. In the end, a robust ammonia reforming system was developed and tested with a PEM fuel cell. The largest energy density achieved, 2.11 Wh g-1 was with the use of a ruthenium catalyst. This energy density is 70% of the maximum energy density for ammonia. In addition the methane autothermal reforming system was investigated. This study utilized a rhodium catalyst bed in alumina reactors. Also, the methane autothermal reforming system was used to collect temperature profiles in a variety of reactor configurations to evaluate heat transfer characteristics. |
