Cyclohexane is a cycloalkane and is non-polar. It is produced by hydrogenation of benzene. Cyclohexane is a colourless, flammable liquid with a distinctive detergent-like odor. Cyclohexane is mainly used for the industrial production of adipic acid and caprolactam, which are precursors to nylon. Cyclohexane is sometimes used as a non-polar organic solvent, although n-hexane is more widely used for this purpose. It is frequently used as a recrystallization solvent in the pharmaceutical industry, as many organic compounds exhibit good solubility in hot cyclohexane and poor solubility at low temperatures.