structural:scholar_edition
Hydrogenation

Hydrogenation, the addition of H to various substrates, is done on a large scale. Hydrogenation of N to produce ammonia by the Haber process, consumes a few percent of the energy budget in the entire industry. The resulting ammonia is used to supply most of the protein consumed by humans. Hydrogenation is used to convert unsaturated fats and oils to saturated (trans) fats and oils. The major application is the production of margarine. Methanol is produced by hydrogenation of carbon dioxide. It is similarly the source of hydrogen in the manufacture of hydrochloric acid. H is also used as a reducing agent for the conversion of some ores to the metals.