الوصف

Diesel fuel is a mixture of hydrocarbons—with boiling points in the range of **0 to **0°C—which are obtained from petroleum. Petroleum crude oils are composed of hydrocarbons of three major classes: (1) paraffinic, (2) naphthenic (or cycloparaffinic), and (3) aromatic hydrocarbons. Unsaturated hydrocarbons (olefins) rarely occur in the crude. It should be noted that the terms paraffinic and naphthenic seem to be obsolescent; we use them because they are still common in the petrochemical industry. In modern chemistry, the respective groups of hydrocarbons are called alkanes and cycloalkanes.