Ethylene oxide: Overview
From polyester to detergents and sterile syringes
What this tab covers What the chemical is, how big its market is, what it is used for (with shares, volumes, why it wins and what could replace it), and its chain from raw material to end user. Ends with three things to remember.Ethylene oxide (EO, C2H4O) is made by reacting ethylene with oxygen over a silver catalyst at about 250°C. World capacity is about 40 Mt a year (indicative), and about 70% of output is hydrated straight into ethylene glycols on the same site. The rest becomes surfactant ethoxylates, ethanolamines, glycol ethers and polyols, or is used to sterilise medical devices. EO is a carcinogen and explosive, so it rarely travels far. Each tonne releases process CO2 from over-oxidation, and cheap pure CO2 makes EO plants early candidates for capture.
Volume about 33-35 Mt produced a year (2025, indicative: about 40 Mt capacity x about 85%) Market value about $35-40 billion a year including captive EO (indicative: about 34 Mt x about $1,100/t) Growth about 3-4% a year, led by polyester and surfactant demand in Asia (indicative) indicative (basis: Argus EO and Derivatives 2025 regional capacity tables, industry estimates); value derivedKey uses
| Use | Share | Annual volume | Why this commodity | Alternatives |
|---|---|---|---|---|
| Ethylene glycols (MEG, DEG, TEG) | 70% | about 24 Mt EObasis | Hydrating EO is the cheapest route to MEG for polyester fibre and PET bottles. About 0.75 t EO makes 1 t MEG, so glycol plants are built alongside EO reactors. indicative (basis: industry splits) | coal-to-MEG via syngas (China) bio-MEG |
| Surfactant ethoxylates | 12% | about 4 Mt EObasis | EO adds water-loving chains to fatty alcohols and nonylphenols, making non-ionic surfactants for detergents, personal care and agrochemicals. indicative | alkyl polyglucosides anionic surfactants such as LAS |
| Ethanolamines | 6% | about 2 Mt EObasis | EO plus ammonia gives mono-, di- and triethanolamine for gas treating, cement grinding aids, detergents and herbicides. Over 90% of China's ethanolamine capacity ran normally in Oct 2025 (Argus). indicative; Argus Oct 2025 | other amines for gas treating |
| Glycol ethers and polyether polyols | 7% | about 2.4 Mt EObasis | Solvents for coatings and brake fluids; EO caps in polyols for flexible polyurethane foam. indicative | propylene oxide-based ethers |
| Sterilisation, PEG and others | 5% | about 1.7 Mt EObasis | EO gas sterilises about half of US medical devices because it works at low temperature on plastics and electronics (indicative, US FDA). Also polyethylene glycols for pharma and cosmetics. indicative (US FDA as known) | gamma and electron beam irradiation hydrogen peroxide plasma |
From raw material to user
- Ethylene and oxygen supply About 0.75 t ethylene and about 0.7 t oxygen per t EO (indicative, stoichiometry at about 87% selectivity), oxygen from an air separation unit.
- Silver-catalysed oxidation Selectivity is about 85-90% with modern catalysts; the rest of the ethylene burns to CO2 and water (indicative).
- CO2 removal and EO recovery A hot potassium carbonate system strips a near-pure CO2 stream of about 0.3-0.4 t per t EO (indicative).
- Glycol or derivative unit About 70% goes straight to glycols on site (indicative).
- Purified EO Shipped short distances by rail or ISO tank under nitrogen, or used for ethoxylation nearby.
Made from (commodity table)
Oil Crude oilGas Natural gasThree things to know
- About 70% of EO never leaves the site as EO; it becomes glycols for polyester (indicative).
- North America has about 8.6 Mt/yr of nameplate EO capacity and Saudi Arabia about 5.7 Mt/yr (Argus estimates, 2025).
- Chinese non-integrated EO producers ran at slightly negative margins, about -$12 to -$14/t, in October 2025 (Argus).