Hydrogenation is a reduction reaction which results in an addition of hydrogen (usually as H2). If an organic compound is hydrogenated, it becomes more "saturated" with hydrogen atoms. The process typically requires the use of a catalyst, since hydrogenation only occurs spontaneously at high temperatures. The most common catalysts are nickel, platinum, or palladium.
Hydrogenation reduces the number of double and triple bonds in hydrocarbons, while dehydrogenation removes hydrogen atoms and increases the number of double and triple bonds.
Key Takeaways: Hydrogenation Definition
- Hydrogenation is a chemical reaction that adds hydrogen to a molecule.
- Hydrogenation is not thermodynamically favorable at ordinary temperatures, so a catalyst is needed. Usually this catalyst is a metal.
- Examples of hydrogenated products include margarine, mineral turpentine, and aniline.
Hydrogenation has many applications, but most people are familiar with the reaction as the one used to make liquid oils into semi-solid and solid fats. There may be some health concerns associated with hydrogenation of unsaturated dietary fats to produce saturated fats and trans fats.
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