ABSTRACT
Hydrocarbons are organic compounds containing only C and H atoms in the molecules. The broad class of organic compounds includes alkanes, alkenes, alkynes, cycloalkanes (naphthenes), and aromatics. Hydrocarbons occurring in nature are natural gases, crude oil, and coals and coal tars, many of which consist of fused polyaromatic rings. Cracking or distillation of crude oil produces various petroleum fractions for their commercial applications. These fractions are distinguished by their carbon numbers, boiling range, and commercial uses and they include gasoline, kerosene, diesel oil, lubricating oil, and wax. These petroleum products may be found in the environment from trace to significant amounts in groundwater, industrial wastewater and sludges, soils, sediments, and solid wastes. Total Petroleum Hydrocarbons (TPHs) and the various petroleum and coal tar fractions in aqueous and nonaqueous samples can be determined by methods based on Infrared (IR) spectrometry and gas chromatography (GC) techniques as follows: gasoline range organics, diesel range organics and polynuclear aromatic hydrocarbons (PAHs).
