Product

Cyclopentane is a highly flammable alicyclic hydrocarbon consisting of a ring of five carbon atoms each bonded with two hydrogen atoms above and below the plane. Cyclopentane is present naturally in straight-run naphtha fractions from crude oil distillation and is a primary component of naphthenic crude oils. It occurs as a colorless liquid with a petrol-like odor. Cyclopentane is in the class of cycloalkanes, being alkanes that have one or more carbon rings.

Production

It can also be produced by catalytic cracking of cyclohexane over alumina at elevated temperature and pressure or by passing 2-methylbutane over a hot Platinum surface. Cyclopentane-rich cuts are separated from light naphtha (C₅ fraction) during refinery operations.

Industrial Uses

A lighter naphthene (bp 49°C), cyclopentane has a growing market as a blowing agent for polyurethane insulating foams (replacing HFC/HFC-134a in refrigerator insulation), driven by its low global warming potential:

• Polyurethane foam blowing agent (primary use): refrigerators, freezers, cold-chain panels, water heaters — cyclopentane is mixed with polyisocyanate and polyol, vaporizes during foaming, and remains trapped in foam cells, providing insulation
• Solvent: non-polar solvent for resins, rubbers, and laboratory use
• Pharmaceutical/natural products extraction: extraction and analysis of bioactive compounds
• Structural motif in biochemistry: the cyclopentane ring is the core of steroids and prostaglandins