open access

https://hdl.handle.net/2115/44811

Self-ignition combustion synthesis of LaNi5 utilizing hydrogenation heat of metallic calcium

英語

Gas-solid reaction

2010-10

ELSEVIER

INTERNATIONAL JOURNAL OF HYDROGEN ENERGY

35(20)

11035-11041

This paper describes self-ignition combustion synthesis (SICS) of LaNi5 in a pressurized hydrogen atmosphere using metallic calcium as both the reducing agent and the heat source. In this study, the effects of hydrogen on the ignition temperature and the hydrogenation properties of the products were mainly examined. In the experiments, La2O3, Ni, and Ca were dry-mixed in the molar ratio of 1:10:6 and then heated up at a hydrogen pressure of 1.0 MPa until the ignition due to the hydrogenation of calcium. For the sake of comparison, the same experiments were performed in a normal argon atmosphere. The results showed that the ignition temperature was drastically lowered by hydrogen; it was only 600 K in the case of hydrogen as compared to 1.100K in the case of argon. The products also exhibited high initial activity and hydrogen storage capacity of 1.54 mass%. The proposed method offers many benefits for using cost-effective rare-earth oxide, saving productive time and energy, improving initial activity of the product and applying to any AB(5)-type hydrogen storage alloy. (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.

学術雑誌論文

Accepted Manuscript

0360-3199

AA00680410