| This thesis focuses on ammonia oxidation processes, specifically hydrogen cyanide synthesis and hydrogen generation. This work stemmed from previous investigations into hydrogen addition to ethane partial oxidation, which had revealed that the use of hydrogen with noble metal catalysts could give improved performance in oxidative dehydrogenation. Based on this discovery and simulations of ethylene synthesis reactions, it was hypothesized that hydrogen addition to the Andrussow process for hydrogen cyanide synthesis would also give superior results. By reacting hydrogen, ammonia, methane, and oxygen over a platinum/rhodium gauze catalyst in a millisecond contact time reactor, and then analyzing the product with a gas chromatograph, this hypothesis was tested. It was found that, as the amount hydrogen fed increased, so too did the hydrogen cyanide selectivity. However, the ammonia conversion decreased significantly over the same range, and as a result the overall yield decreased with increasing hydrogen fed.; Following these hydrogen cyanide synthesis experiments, work began on a project to generate hydrogen through ammonia reforming. Fuel cell technology necessitates a readily available, inexpensive source of hydrogen; many feel that this hydrogen can be obtained from ammonia. It was hoped that by catalytically oxidizing ammonia, large amounts of hydrogen could be produced at high ammonia conversions. By varying the ammonia/oxygen feed ratio, the catalyst used, and the reactor configuration, it was found that hydrogen yields in excess of 60% could be obtained at ammonia conversions of 99%. This product stream is suitable for use in a P.E.M. fuel cell. |
