N. Nakamura et al. / Journal of Alloys and Compounds 580 (2013) S410–S413
S413
temperature and low reaction yield were also problems. It is
Acknowledgement
thought that these problems were caused by low-vapor pressure
of Li at around 500 °C, in other words, more than 800 °C would
be required to generate sufficient amount of Li vapor for control-
ling the reaction entropy. Thus, the reaction system for producing
nonequilibrium state should be improved to control the reaction at
lower temperature.
The hydrolysis reaction (3) is exothermic. In the experiment, the
reaction between Li2O2 and H2O was carried out at 300 °C. Fig. 4
shows the XRD patterns of the starting material and the products.
As shown in the upper XRD pattern, the commercial Li2O2 con-
tained a small amount of LiOH as an impurity. After the hydrolysis
reaction, it was confirmed that Li2O2 was completely changed to
LiOH, indicating that the hydrolysis reaction proceeded. In addi-
tion, it was clearly clarified by GC that the gaseous product was
O2. These results indicate that 300 °C is sufficient for completing
the hydrolysis reaction.
This work was partially supported by General Sekiyu R&D
Encouragement Assistance Foundation.
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4. Conclusions
In this work, the reaction conditions of water-splitting by the Li
system were investigated. Particularly, a nonequilibrium process
was adopted to control the entropy and then lower the reaction
temperature. The reaction (1) between LiOH and Li completely pro-
ceeded at 500 °C with the formation of Li2O and H2. For reaction
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as the expected products.
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