Paracetamol: Production route
Three ways to make the same simple molecule
What this tab covers How it is made: the main production routes or, for product families, the main product types and technologies, compared on share of supply, inputs per tonne, plant scale, yield, co-products and unit cost.All commercial paracetamol is made by acetylating PAP; routes differ in how PAP is made. The dominant PAP route hydrogenates nitrobenzene in sulphuric acid. An older route nitrates phenol and reduces p-nitrophenol. A third route, developed by Hoechst Celanese, acylates phenol to 4-hydroxyacetophenone and converts its oxime to paracetamol by Beckmann rearrangement, avoiding PAP. Cost is set by benzene, acetic anhydride, hydrogen and energy.
Routes compared
| Route | Share of supply | Inputs per tonne | Typical scale | Yield | Co-products | Unit cost |
|---|---|---|---|---|---|---|
| Nitrobenzene hydrogenation to PAP, then acetylation | main route (indicative) | about 0.8 t nitrobenzene per t paracetamol, 0.68 t acetic anhydride (stoichiometric 0.81 and 0.68; indicative) | PAP plants 5,000-15,000 t/yr; Meghmani 13,500 t/yr | not published | aniline, ammonium sulphate, acetic acid (recycled) | India API price about $2,958/t (Q2 2025, IMARC) |
| Phenol nitration and reduction | minority (indicative) | about 0.62 t phenol per t at 100% yield (stoichiometric) | not published | lower because of isomer split | o-nitrophenol, iron sludge if iron reduction used | not published |
| Hoechst Celanese route (4-hydroxyacetophenone oxime) | small (indicative) | not published | not published | high selectivity | fewer salts | not published |
How each route works
Nitrobenzene hydrogenation to PAP, then acetylationNitrobenzene is hydrogenated over platinum in dilute sulphuric acid; the phenylhydroxylamine formed rearranges to PAP (Bamberger). PAP is purified and acetylated with acetic anhydride.
cheapest route; acid effluent
PSU Watch (2026); IMARC (2025); stoichiometry Phenol nitration and reductionPhenol is nitrated to a mix of ortho and para nitrophenol; the para isomer is reduced (iron-acid or catalytic hydrogen) to PAP, then acetylated.
simple chemistry; more waste
stoichiometry Hoechst Celanese route (4-hydroxyacetophenone oxime)Phenol is acylated with acetic anhydride in HF to 4-hydroxyacetophenone, converted to its oxime with hydroxylamine and rearranged to paracetamol.
atom-efficient but uses HF
qualitative Unit economics are indicative ranges from the sources named; costs move with feedstock and energy prices, plant size and region.