2016 Volume 57 Issue 7 Pages 1215-1219
Lithium hydride-Potassium hydride (LiH-KH) composite prepared by ball-milling is focused in order to modify the kinetic properties of the reaction between LiH and gaseous ammonia (NH3). The LiH-NH3 system is recognized as one of the most promising hydrogen storage system because it generates hydrogen at room temperature by ammonolysis reaction, is regenerated below 300℃, and possesses more than 8.0 mass% hydrogen capacity. From the experimental results, it is confirmed that the hydrogen generation from the reaction between NH3 and the LiH-KH composite shows much higher reaction rate than that of the simple summation of each component, which can be recognized as a synergetic effect. Then, double-cation metal amide (MNH2) phases such as LiK(NH2)2, which are not assigned to any amides reported before, are formed as the reaction product. Moreover, it is confirmed that hydrogenation of the generated amide can proceed to form LiH-KH composite and NH3.
