Hydrogen is used:

  1. for conversion of coal into synthetic petroleum.
  2. in the manufacture of bulk organic chemicals, particularly methanol.
  3. in the hydrogenation of oils. Vegetable oils change in to vegetable ghee when hydrogen is passed through the oils at 443 K in presence of nickel as catalyst.
  4. in the manufacture of ammonia, which is used in the production of fertilizers.
  5. as primary fuel for heavy rockets.
  6. for filling balloons.