cyclohexane(redirected from Cyclohexanes)
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cyclohexane(sī'kləhĕk`sān), C6H12, colorless liquid hydrocarbon. It is a cyclic alkane that melts at 6°C; and boils at 81°C;. It is nearly insoluble in water. Cyclohexane is found naturally to some extent in petroleum but is prepared commercially by catalytic hydrogenation of benzene. It is widely used as a solvent and in making certain compounds used in the preparation of nylon.
a saturated alicyclic hydrocarbon. A cycloalkane, cyclohexane has the structural formula
It is a colorless liquid with a characteristic odor. It has a melting point of 6.55°C, a boiling point of 80.74°C, and a density of 0.778 g/cm3 at 20°C. Insoluble in water, cyclohexane is miscible with ether, acetone, and benzene. It has two possible conformations —the “boat” and “chair” forms; the latter predominates at normal temperatures.
Cyclohexane is a component of virtually all petroleums, but it is present only in small amounts. It is therefore produced in industry mainly by the catalytic hydrogenation of benzene. It is used as a raw material for the production of cyclohexanol and cyclohexanone (by oxidation with oxygen), nitrocyclohexane (by the action of 30-percent nitric acid or nitrogen dioxide), and cyclohexanone oxime (by nitrosation using NOCl); all of these substances are intermediates in the production of caprolactam and adipic acid by catalytic oxidation. Both caprolactam and adipic acid are used in the production of polyamides.