12Epoxypropane

1,2-Epoxypropane, commonly known as propylene oxide or methyloxirane, is a small, three-membered cyclic ether (an epoxide) with the molecular formula C3H6O. It is a colorless, volatile liquid with a faintly sweet odor and a relatively low boiling point. The strained epoxide ring makes the molecule highly reactive toward nucleophiles, a property that underlies its industrial utility.

Commercial production of 1,2-epoxypropane is carried out by oxidation of propylene. Historically the chlorohydrin route was common, but modern processes favor direct oxidation using organic hydroperoxides or hydrogen peroxide (the HPPO process) because they generate fewer byproducts and lower waste. The compound is handled and transported as a stabilized liquid, often with inhibitors to prevent runaway polymerization.

The principal use of propylene oxide is as an intermediate in the manufacture of propylene glycol, polyether polyols (for polyurethane production), and glycol ethers. It also serves in the production of surfactants, lubricants, and as an alkylating agent in various chemical syntheses. Limited specialist uses have included fumigation and sterilization, but these declined due to safety concerns.

1,2-Epoxypropane is flammable, irritating to the eyes and respiratory tract, and toxic at high exposures. It can cause central nervous system effects and sensitization. International agencies have classified it as possibly carcinogenic to humans. Industrial hygiene measures—closed systems, explosion-proof equipment, adequate ventilation, and personal protective equipment—are recommended to minimize exposure.