isoparaffins

Isoparaffins, also called isoalkanes, are a class of branched saturated hydrocarbons within the paraffin family. They are isomers of n-alkanes, sharing the general formula CnH2n+2 but with one or more branches in the carbon chain. The term encompasses a range of compounds from light to heavy paraffins, including well-known examples such as isopentane (2-methylbutane), isohexane (2-methylpentane), and isooctane (2,2,4-trimethylpentane).

In refining and petrochemical processes, isoparaffins are produced by isomerization of n-paraffins and related rearrangement steps during catalytic reforming or hydrocracking. They are a major component of isoparaffinic solvent fractions and of certain gasoline blends. The branched structure generally imparts lower boiling points and different freezing behavior compared with straight-chain isomers of the same carbon number, contributing to desirable properties in fuels and solvents.

Uses and applications are diverse. In fuels, certain isoparaffins contribute to octane rating; isooctane has historically served as a standard reference fuel for anti-knock performance. In solvents, isoparaffinic products are valued for relatively good solvency for nonpolar materials, low aromatic content, and good compatibility with many coatings, inks, and cleaners. They are commonly employed where a low-aromatic, low-odor solvent is preferred.

Safety and handling follow standard hydrocarbon solvent practices. Isoparaffins are flammable and can act as irritants or asphyxiants in high concentrations; appropriate precautions, ventilation, and containment are advised.