|Molar mass||98.15 g/mol|
|Odor||peppermint or acetone-like|
|Density||0.9478 g/mL, liquid|
|Melting point||−47 °C (−53 °F; 226 K)|
|Boiling point||155.65 °C (312.17 °F; 428.80 K)|
|8.6 g/100 mL (20 °C)|
|Solubility in all organic solvents||Miscible|
|Vapor pressure||5 mmHg (20°C)|
Refractive index (nD)
|Viscosity||2.02 cP at 25 °C|
Std enthalpy of
|−270.7 kJ mol−1|
Std enthalpy of
|EU classification||Harmful (Xn)|
|Flash point||44 °C (111 °F; 317 K)|
|420 °C (788 °F; 693 K)|
|US health exposure limits (NIOSH):|
|TWA 50 ppm (200 mg/m3)|
|TWA 25 ppm (100 mg/m3) [skin]|
LDLH (Immediate danger)
Except where noted otherwise, data is given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
|what is: / ?)(|
Cyclohexanone is the organic compound with the formula (CH2)5CO. The molecule consists of six-carbon cyclic molecule with a ketone functional group. This colorless oil has an odor reminiscent of peardrop sweets as well as acetone. Over time, samples assume a yellow color due to oxidation. Cyclohexanone is slightly soluble in water, but miscible with common organic solvents. Billions of kilograms are produced annually, mainly as a precursor to nylon.
- C6H12 + O2 → (CH2)5CO + H2O
This process co-forms cyclohexanol, and this mixture, called "KA oil" for ketone-alcohol oil, is the main feedstock for the production of adipic acid. The oxidation involves radicals and the intermediacy of the hydroperoxide C6H11O2H. In some cases, purified cyclohexanol, obtained by hydration of cyclohexene, is the precursor. Alternatively, cyclohexanone can be produced by the partial hydrogenation of phenol:
- C6H5OH + 2 H2 → (CH2)5CO
This process can also be adjusted to favor the formation of cyclohexanol.
Cyclohexanone can be prepared from cyclohexanol by oxidation with chromium trioxide (Jones oxidation). An alternative method utilizes the safer and more readily available oxidant sodium hypochlorite.
The great majority of cyclohexanone is consumed in the production of precursors to Nylon 6,6 and Nylon 6. About half of the world's supply is converted to adipic acid, one of two precursors for nylon 6,6. For this application, the KA oil (see above) is oxidized with nitric acid. The other half of the cyclohexanone supply is converted to the oxime. In the presence of sulfuric acid catalyst, the oxime rearranges to caprolactam, a precursor to nylon 6:
A recent study of plastic tubing used in medical procedures that circulate blood outside the body suggests a link between this compound and decreased heart function, swelling, loss of taste and short term memory loss.
- International Chemical Safety Card 0425
- NIOSH Pocket Guide to Chemical Hazards
- "NIOSH Pocket Guide to Chemical Hazards". National Institute for Occupational Safety and Health (NIOSH). id=0166.
- Data extract from Landolt-Börnstein IV/25: Viscosity of Pure Organic Liquids and Binary Liquid Mixtures
- Sigma-Aldrich - Cyclohexanone
- Michael T. Musser "Cyclohexanol and Cyclohexanone" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2005.doi:10.1002/14356007.a08_217