Question
How HNO3 is manufactured by Ostwald’s process?
Answer
HNO3 is manufactured by Ostwald’s Process, which involves the following steps:
- Ammonia (NH3) is oxidized to nitrogen monoxide (NO) by heating it in the presence of a platinum-rhodium catalyst at a temperature of around 850-900°C.
4NH3 (g) + 5O2 (g) → 4NO (g) + 6H2O (g)
- The nitrogen monoxide is then oxidized to nitrogen dioxide (NO2) by reacting it with excess oxygen in the presence of a platinum-rhodium catalyst at a temperature of around 450-550°C.
2NO (g) + O2 (g) → 2NO2 (g)
- The nitrogen dioxide is then absorbed in water to form nitric acid (HNO3), which is then concentrated to the desired strength through distillation.
3NO2 (g) + H2O (l) → 2HNO3 (aq) + NO (g)