Hydrogen – Where can we get?
- •Hydrogen is not available in nature in as hydrogen.
- •It is available as in combination with other elements
How do we make Hydrogen now ?
- We make about 9 billion tons/year
- 95% is used by chemical, metals, electronics and space industries
- Current production methods
- From methane using steam (80%)
- CH4 + 2H2O -> 4H2 + CO2
–1,100 C in presence of a catalyst
Relatively efficient and inexpensive process
Emissions of carbon dioxide ?
Fluctuating cost of natural gas
- By product from Chlor-Alkali Production (20%)
- 2 NaCl (aq) + 2 H2O (l) ---> H2 (g) + Cl2 (g) + 2 NaOH (aq)
- –Electrolysis (negligible)
- 2H2O (l) → 2H2 (g) + O2 (g)
- •237.17 kJ/mole of electrical energy is req’d plus 48.7 kJ/mole of energy from the environment