2021 年 46 巻 4 号 p. 269-278
Ammonia (NH3) is recognized as an attractive hydrogen (H2) and energy carriers because it has a high gravimetric H2 density of 17.8 wt% and highest volumetric H2 density of 10.7kgH2/100L. The gravimetric H2 density is third largest after NH3BH3 and LiBH4. The volumetric hydrogen density is 1.5-1.7 times of liquid hydrogen, and it is easily liquefied under about 1 MPa at room temperature. NFPA flammability of NH3 is low because of the high flash point. NH3 and liquid H2 have a same high NFPA health hazard of 3. Proton-based solid acids such as zirconium phosphate for the vapor concentration (vapor pressure) and the nitrogen concentration in water lowering will be used to reduce the negative effects on the environment. Green ammonia will be synthesized using renewable energy (renewable electricity), water, air and Haber–Bosch process. Ammonia for fuel has advantages as an energy carrier for electric power plants, industrial furnaces, bunker fuel, solid oxide fuel cell (SOFC) and a hydrogen carrier for mobilities.
