Page 14 - Introduction to Transfer Phenomena in PEM Fuel Cells

Introduction to Hydrogen Technology 3

Figure 1.2. Comparison of HCV and LCV for various fuels [AUP 13]

Properties Hydrogen Methane Methanol Ethanol Propane Gasoline
Molecular mass (g/mol) 2.016 16.043 32.04 46.06 44.1 ~107
3
Volumic mass (kg/m ) 0.08375 0.6682 791 789 1.865 751
at 20°C
Boiling point (°C) −252.8 −161.5 64 78.5 −42.1 27-225
Flash point (°C) –253 −188 11 13 −104 −43
Flammability limits in air
4.0–75.0 5.0–15.0 6.7–36.0 3.3–19 2.1–10.1 1.0–7.6
(% volume)
CO 2 produced per unit 0 1 1.5 180
energy
Auto-ignition temperature
585 540 385 423 490 230–480
in air (°C)
Higher calorific value 142 55.5 22.9 29.8 50.2 47.3
(MJ/kg)
Lower calorific value
120 50 20.1 27 46.3 44
(MJ/kg)

Table 1.1. Fuel comparison