Harnstoffsynthese aus Ammoniak und Kohlendioxid

Urea is the world's most widely used solid nitrogen fertilizer, produced by reacting ammonia with carbon dioxide at high temperature and pressure. The process conveniently uses the CO2 byproduct from hydrogen production in ammonia synthesis, making urea plants typically co-located with ammonia plants. Urea contains 46% nitrogen (the highest of any solid fertilizer), is non-explosive, highly water-soluble, and easy to handle and apply. It is also used in animal feed, urea-formaldehyde resins, and diesel exhaust fluid (DEF/AdBlue).

Urease inhibitors (NBPT) applied to urea granules reduce ammonia volatilization by 50%.
Polymer-coated urea provides controlled nitrogen release matching crop demand.
CO2 capture from flue gas for urea production could expand supply while reducing emissions.