Estimation of Enthalpy of Formation of Metal Hydrides: Effect of Different Measurement Parameters
- 36 Downloads
The enthalpy of formation of metal hydrides is estimated by van’t Hoff equation. Pressure-concentration isotherms (PCIs) at different temperatures are used to obtain van’t Hoff plots. Enthalpy of formation is an important input in simulation and performance estimation of metal hydride-based engineering devices. The absolute error in the measurement of enthalpy of formation depends upon the relative error of PCI measurements. The error in the estimation of this quantity depends upon the number of temperature points used for obtaining van’t Hoff plots and, temperature range and size of the range. In the present study, PCIs of MmNi3.5Co0.8Al0.7 hydride were measured in the temperature range of 20–240 ℃. The effect of number of temperature points, temperature range and size of the range on the estimation of enthalpy of formation is studied. The effect of the temperature range and size of the range are found to be more sensitive in the estimation of enthalpy of formation.
KeywordsEnthalpy of formation Van’t Hoff plot PCIs Metal hydride
- 4.G. Balachandran, U. Krishna Prasad, M.V. Ananth, M.V.S. Suryanarayana, Metallurgical characteristics of AB5 intermetallic alloys developed for hydrogen storage applications. International conference on solid state hydrogen-storage and applications, Hyderabad, India, 2005Google Scholar