Liquefaction and Compression of Hydrogen

Energy is needed to eompress gases. The compression work depends on the thermodynamic compression process. The ideal isothermal compression cannot be realized. Even more energy is needed to compact hydrogen by liquefaction. Low density and extremely low boiling point of hydrogen increases the energy cost of compression or hquefaction. 

The activated hydrogen molecules can be attracted to each other more than normal hydrogen molecules in the reaction medium and these attractions may result easily in liquefaction of hydrogen in reaction conditions (Fig. 5.12). 

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