Numerical simulation of micromixing in Beckmann rearrangement of cyclohexanone oxime was carried out with engulfment-deformation-diffusion model by taking into account the reaction kinetics.The effects of key industrial parameters on the reaction and mass transfer were investigated.The results showed that Beckmann rearrangement was micromixing controlled and the local molar ratio of acid to oxime was lower than the value in macro-scale process

which deviated from the normal reaction condition and explained the difference between the theoretical minimum acid amount and industrial value.Higher temperature leaded to poor quality of product though it was in favor of molecular diffusion.Decrease in the diameter of mixer resulted in better micromixing to some extent

which may improve mass transfer and the quality of caprolactam.