Site items in: Content by Author Hiroki Muroyama

Presentation

Hydrogen is the primary fuel source for fuel cells. However, the low volume density and difficulty in storing and transporting hydrogen are major obstacles for its practical utilization. Among various hydrogen carries, ammonia is one of the most promising candidates because of its high hydrogen density and boiling point and ease in liquefaction and transportation. The reaction temperature of ammonia cracking into nitrogen and hydrogen is about 500˚C or higher. The hydrogen can be effectively separated by the membrane based on Pd alloy about 500˚C. Currently, the extraction of hydrogen from ammonia is carried out by two step process involving…

Presentation

Ammonia is a promising hydrogen carrier because of its high hydrogen density, low production cost, and ease in liquefaction and transport. Ammonia decomposes into nitrogen and hydrogen through a mildly endothermic process. The ammonia decomposition temperature is close to the operating conditions of solid oxide fuel cells (SOFCs). Therefore, the integration of these two devices is beneficial in terms of efficient heat and energy managements and will lead to the development of simplified generation systems. We have investigated three types of ammonia-fueled SOFC systems. In one system, ammonia is directly supplied to the anode chamber. Ammonia decomposes into nitrogen and…

Presentation

Current progress in development of NH3-fueled solid-state fuel cell systems T. Okanishi*, K. Okura, J. Yang, H. Muroyama, T. Matsui, M. Kishimoto, M. Saito, H. Iwai, H. Yoshida, K. Eguchi, Kyoto University; H. Iwai, K. Inaoka, S. Suzuki, Y. Takahashi, Noritake; T. Horiuchi, H. Yamasaki, Nippon Shokubai; S. Matsumoto, H. Kubo, Toyota Industries; J. Kawahara, A. Okabe, Mitsui Chemical; Y. Kikkawa, T. Negishi, S. Watanabe, Tokuyama

Presentation

Ammonia is a prospective carbon-free fuel source for fuel cell systems due to low production cost, ease in liquefaction at ambient temperatures, and high energy density. Furthermore, hydrogen and nitrogen originating from ammonia fuel are expected to have little negative effect on fuel cell performance, while hydrocarbon fuels draws some severe problems at electrodes, such as CO poisoning or carbon deposition in low- and high-temperature fuel cells, respectively. Several technologies can be considered for the ammonia utilization in fuel cell systems. For the utilization of ammonia fuel, we aim to develop a system combined with ammonia decomposition reactor and solid-state…