What does dehydrogenation mean?
Dehydrogenation is a noun referring to the chemical removal of hydrogen from a compound. It is essentially the reverse of hydrogenation, which adds hydrogen, and it underpins some of the most important processes in modern industry and biology. Industrially, dehydrogenation is used on an enormous scale: converting butane into butadiene for synthetic rubber, ethylbenzene into styrene for plastics, and propane into propylene for countless polymer products. These transformations typically require high temperatures and carefully chosen catalysts, such as chromium or iron oxides. In biochemistry, dehydrogenation describes reactions in which enzymes called dehydrogenases strip hydrogen atoms from molecules like glucose derivatives, transferring them to electron carriers such as NAD⁺ — a key step in how cells extract energy from food. Because the word is confined to scientific registers, it carries a precise, neutral connotation rather than any emotional coloring. For students of chemistry, it is a useful marker term: wherever you see it, a molecule has lost hydrogen, and its structure and reactivity have changed accordingly.
nounThe chemical process of removing hydrogen from a compound, typically by heating or with a catalyst, as in converting alcohols to aldehydes or ketones. It is the reverse of hydrogenation.
- The process of removing hydrogen from a chemical compound, especially industrially or in organic chemistry.
- In biochemistry, a step in cellular metabolism in which enzymes (dehydrogenases) remove hydrogen atoms from substrates, as in the reactions of the citric acid cycle.
"The dehydrogenation of ethylbenzene over an iron oxide catalyst yields styrene, the raw material for polystyrene."
"Catalytic dehydrogenation of propane is now a major industrial route to propylene."
"During the citric acid cycle, successive dehydrogenations transfer electrons to NAD⁺ and FAD."
The plural is rare and used mainly in biochemistry to refer to multiple distinct enzymatic dehydrogenation steps within a pathway; the singular uncountable form is standard for the general process.
"The citric acid cycle involves four oxidative dehydrogenations per turn."
Every styrofoam cup and plastic spoon you've touched likely began life in a dehydrogenation reactor, where steam-heated catalysts strip hydrogen from petrochemicals at hundreds of degrees.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of dehydrogenation
Dehydrogenation is formed from the prefix de- (indicating removal), the root hydrogen — itself coined in the late 18th century by French chemists Lavoisier and colleagues from Greek hydōr ('water') and gennan ('to generate'), because burning hydrogen produces water — plus the noun-forming suffix -ation. The word arose in 19th-century European chemistry as scientists developed systematic nomenclature for reaction types. Its Greek-derived components give it cognates across chemistry, including hydrogenation, hydration, and dehydration, all built on the same hydro- root.
Related word forms
How dehydrogenation is actually used
A technical term used almost exclusively in chemistry, chemical engineering, and biochemistry; it does not occur in general everyday language. In industrial contexts it often appears in compounds such as "oxidative dehydrogenation" or "steam dehydrogenation," specifying the method used. The related enzyme names end in -ase (e.g., dehydrogenase), not -ation.
Easily confused with dehydrogenation
Dehydration removes water (or the elements of water) from a substance, whereas dehydrogenation removes only hydrogen.
Hydrogenation adds hydrogen to a compound, while dehydrogenation removes it.