Studies On The Nitrosation Kinetic Of Cyclohexanecarboxylic Acid

Caprolactam is an important petrochemical and it is mainly used for manufacture of engineering plastic and fibre for public and industry. There has been more than ten years since caprolactam is produced on industrial scales in China. However, for the specialty and sophistication of this process, there are still many problems in this chemical process. The nitrosation of cyclohexanecarboxylic acid with nitrosyl sulfuric acid is a key step of the industrial way which toluene is used as raw material to produce caprolactam. Aiming at the nitrosation in the SNIA technics, the paper has done some work as follows. Aiming at the nitrosation process of cyclohexanecarboxylic acid, three verification experiments were designed, and the experiments showed that the main vice-reaction is a parallel reaction between CCA and SO3 as well as a series reaction between caprolactam and nitrosyl sulfuric acid respectively relative to the nitrosation. Then the kinetic data of the nitrosation reaction and the main vice-reactions had been measured. The second, a reaction kinetic model of the process was proposed based on the careful analysis and reasonable simplification of the nitrosation process and the model parameters were indirectly determined by the results of decomposition-colligation experiments on the assumption that all the components in the nitrosation system have no intercrossing influnce in the reactions. On the reaction kinetic model and the model parameters, the influence of reaction term to reaction yield was discussed. The dependability of the reaction kinetic model was verified by the experiment under the optimum reaction term. The model could indicate the characteristic of the CCA nitrosation reaction process and provide a relative dependable support for the design and optimization of the industrial process.