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How does the Haber-Bosch process use nitrogen from the atmosphere?

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Wispy cirrus clouds stretch across a bright blue sky above trees and a river at Pinawa Dam Provincial Park in Manitoba, Canada, with sunlight illuminating the scene. — Atmosphere The atmospheres of planets in the solar system are composed of various gases, particulates, and liquids. They are also dynamic places that redistribute heat and other forms of energy. On Earth, the atmosphere provides critical ingredients for living things. Here, feathery cirrus clouds drift across the deep blue sky over Pinawa Dam Provincial Park, near Pinawa, Manitoba, Canada.

The Haber-Bosch process utilizes nitrogen from the atmosphere by directly combining it with hydrogen to synthesize ammonia. Because atmospheric nitrogen is a relatively inert gas, it does not react easily under ordinary conditions. To overcome this, the process employs extreme conditions to force a chemical reaction.12

In this industrial method, air—which serves as the source of nitrogen—is processed alongside hydrogen under high pressures ranging from 200 to 400 atmospheres and temperatures between 400° and 650° C (750° to 1200° F). An iron-based catalyst is used to enable the reaction at these temperatures, which are more practical than those that would otherwise be required.1

As the gases pass through converters, a portion of the nitrogen and hydrogen combines to form ammonia. This product is removed from the system, and the remaining gases are recycled to maintain an equilibrium that favors further production. This process is the most economical method for the fixation of nitrogen, allowing for the large-scale manufacture of essential nitrogen compounds.312