OU Kui-yi¹,  ZENG Zhen¹,  WANG Liang-jie¹,  LIU Ping-le¹,  WU Jian¹,  LI Song¹,  YIN Du-lin²,  LUO He-an¹

(1.College of Chemical Engineering, Xiangtan University; Engineering Research Center of Chemical ProcessSimulation & Optimization of Ministry of Education, Xiangtan 411105, China; 2.College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, China)

Abstract:  The liquid phase Beckmann rearrangement of cyclohexanone oxime into ε-caprolactam was successfully developed by using D-72 sulfonic acid resin as catalyst and dimethylsulfoxide as solvent in a two-phase system. The effect of solvent, reaction temperature, reaction time and amount of catalyst on the rearrangement of cyclohexanone oxime were examined. The results indicate that the adsorption behavior of cyclohexanone oxime on sulfonic acid resin accords with Langmuir adsorption model and can be described by Langmuir isotherm and speed equation. And the conversion of cyclohexanone oxime can reach 100% with 86.2% of selectivity to ε-caprolactam when the reaction was carried out at 130 ℃ for 6 h in dimethylsulfoxide solvent (m (catalyst)∶m (oxime) =1∶2 (mass ratio)). This catalytic system involved environmentally harmless, mild reaction conditions, and the catalyst can be conveniently recovered for recycled use.

Key words: D-72 sulfonic acid resin; Dimethylsulfoxide; Liquid phase Beckmann rearrangement; Cyclohexanone oxime; ε-Caprolactam

E-mail: hluo@ xtu. edu. cn

Journal of Molecular Catalysis, Vol. 24, Issue 4, 2010, 327~332