Caprolactam

Abstract

The article contains sections titled: 1. History 2. Physical Properties 3. Chemical Properties 4. Production 4.1. Processes via Cyclohexanone 4.1.1. Cyclohexanone Oxime 4.1.2. Beckmann Rearrangement to Caprolactam 4.1.3. Improvement of the Oximation Process 4.1.4. Gas‐Phase or Catalytic Rearrangement of Cyclohexanone Oxime 4.1.5. Modified Oximation and Beckmann Rearrangement 4.2. Photooximation 4.3. Production from Toluene 4.4. Recovery from Nylon‐6 Waste 4.5. Former Commercial Routes 4.6. New Routes in Development 4.7. Environmental Protection 5. Quality Specifications 6. Analysis 7. Storage and Transportation 8. Economic Aspects 9. Toxicology

Impurity Formation in the Beckmann Rearrangement of Cyclohexanone Oxime to Yield ε-Caprolactam

“…Another possible reason is that the mixing performance is enhanced as a result of the decrease in viscosity from 1800 to 500 mPa·s as the A/O ratio is increased from 0.8 to 1.2 and even to 150 mPa·s at an A/O ratio of 1.6 . These results account for the fact that the A/O ratio should be maintained between 1.2 and 1.7 in the current industrial process. , …”

Impurity Formation in the Beckmann Rearrangement of Cyclohexanone Oxime to Yield ε-Caprolactam

“…Another possible reason is that the mixing performance is enhanced as a result of the decrease in viscosity from 1800 to 500 mPa·s as the A/O ratio is increased from 0.8 to 1.2 and even to 150 mPa·s at an A/O ratio of 1.6 . These results account for the fact that the A/O ratio should be maintained between 1.2 and 1.7 in the current industrial process. , …”

Beckmann Rearrangement with Improved Atom Economy, Catalyzed by Inexpensive, Reusable, Bro̷nsted Acidic Ionic Liquid

“…All the ILs dissolved the oxime, and hence, it was possible to use them as solvents as well as catalysts. However, the cyclohexanone oxime rearrangement is a highly exothermic reaction (1815 kJ/kg), and a strong exothermic effect was observed in preliminary experiments on a 10 g scale. In consequence, n -octane was introduced as a second solvent, for safety reasons.…”

Organocatalyzed Synthesis and Antibacterial Activity of Novel Quinolino Annulated Analogues of Azepinones

“…Besides requiring high temperature, the latter reactions also produce huge amounts of hazardous by‐products . Synthesis of nylon‐6 from ϵ‐caprolactam is one such example that employs the use of fuming sulfuric acid and produces ammonium sulfate as by‐product .…”

Impurity Formation in the Beckmann Rearrangement of Cyclohexanone Oxime to Yield ε-Caprolactam

“…Another possible reason is that the mixing performance is enhanced as a result of the decrease in viscosity from 1800 to 500 mPa·s as the A/O ratio is increased from 0.8 to 1.2 and even to 150 mPa·s at an A/O ratio of 1.6 . These results account for the fact that the A/O ratio should be maintained between 1.2 and 1.7 in the current industrial process. , …”

Beckmann Rearrangement with Improved Atom Economy, Catalyzed by Inexpensive, Reusable, Bro̷nsted Acidic Ionic Liquid

“…All the ILs dissolved the oxime, and hence, it was possible to use them as solvents as well as catalysts. However, the cyclohexanone oxime rearrangement is a highly exothermic reaction (1815 kJ/kg), and a strong exothermic effect was observed in preliminary experiments on a 10 g scale. In consequence, n -octane was introduced as a second solvent, for safety reasons.…”

Organocatalyzed Synthesis and Antibacterial Activity of Novel Quinolino Annulated Analogues of Azepinones

“…Besides requiring high temperature, the latter reactions also produce huge amounts of hazardous by‐products . Synthesis of nylon‐6 from ϵ‐caprolactam is one such example that employs the use of fuming sulfuric acid and produces ammonium sulfate as by‐product .…”

Impurity Formation in the Beckmann Rearrangement of Cyclohexanone Oxime to Yield ε-Caprolactam

“…Another possible reason is that the mixing performance is enhanced as a result of the decrease in viscosity from 1800 to 500 mPa·s as the A/O ratio is increased from 0.8 to 1.2 and even to 150 mPa·s at an A/O ratio of 1.6 . These results account for the fact that the A/O ratio should be maintained between 1.2 and 1.7 in the current industrial process. , …”

Beckmann Rearrangement with Improved Atom Economy, Catalyzed by Inexpensive, Reusable, Bro̷nsted Acidic Ionic Liquid

“…All the ILs dissolved the oxime, and hence, it was possible to use them as solvents as well as catalysts. However, the cyclohexanone oxime rearrangement is a highly exothermic reaction (1815 kJ/kg), and a strong exothermic effect was observed in preliminary experiments on a 10 g scale. In consequence, n -octane was introduced as a second solvent, for safety reasons.…”

Organocatalyzed Synthesis and Antibacterial Activity of Novel Quinolino Annulated Analogues of Azepinones

“…Besides requiring high temperature, the latter reactions also produce huge amounts of hazardous by‐products . Synthesis of nylon‐6 from ϵ‐caprolactam is one such example that employs the use of fuming sulfuric acid and produces ammonium sulfate as by‐product .…”