The Haber Process industrially prepares ammonia. It combines nitrogen from the air with hydrogen under high pressure and elevated temperature, using an iron-based catalyst: N₂ + 3H₂ ⇌ 2NH₃.
German chemist Fritz Haber developed the laboratory process, and engineer Carl Bosch adapted it for large-scale industrial production. BASF began operating the first industrial plant at Oppau, Germany, in 1913. The process solved a major agricultural problem by turning abundant atmospheric nitrogen into ammonia, the starting material for many nitrogen fertilizers.
The reaction is reversible and exothermic, so industrial plants balance pressure, temperature, and catalyst performance rather than simply maximizing one factor. Ammonia is separated from the reaction mixture, while unreacted nitrogen and hydrogen are recycled. Although the process is often called the Haber-Bosch process, “Haber Process” is the standard quiz answer.
Ammonia is also used to make nitric acid, explosives, plastics, and cleaning products. The process transformed food production, but its reliance on hydrogen commonly made from natural gas gives it a substantial energy and carbon footprint.