Production of Ammonia (Oxford AQA IGCSE Chemistry)

The Haber Process

• Ammonia is manufactured using the Haber Process

• The reactants are hydrogen and nitrogen

  • Hydrogen is obtained from natural gas (methane) or other sources

  • Nitrogen is obtained from the air

• Ammonia is a raw material in the production of fertilizers

  • There is a high demand globally for fertilizers in order to maximise food yields

The Haber Process

• Stage 1: H₂ and N₂ gases are pumped into the compressor through pipes

• Stage 2: The gases are compressed to about 200 atmospheres inside the compressor catalyst at a temperature of 450°C. Some of the hydrogen and nitrogen react to form ammonia in the following reversible reaction:

N₂ (g) + 3H₂ (g) ⇌ 2NH₃ (g)

• Stage 4: Unreacted H₂ and N₂ and product ammonia pass into a cooling tank. The ammonia is liquefied and removed to pressurised storage vessels

• Stage 5: The unreacted H₂ and N₂ gases are recycled back into the system

The Haber Process