Preparation of SiO2–Al2O3 and Its Supported Co3O4 Catalysts for Nitrosation of Cyclohexane

Abstract

Amorphous SiO2–Al2O3 was prepared by sol–gel method and cobalt oxide supported on SiO2–Al2O3 was prepared by impregnation method. These materials were characterized by BET, XRD, TPD and FT-IR. The activity of SiO2–Al2O3 and Co3O4/SiO2–Al2O3 catalysts for nitrosation of cyclohexane with nitrosyl sulfuric acid in the presence of fuming sulphuric acid was evaluated. The results indicate that SiO2–Al2O3 and Co3O4/SiO2–Al2O3 can catalyze efficiently this nitrosation reaction. And Co3O4/SiO2–Al2O3 gave better results with 11.93% of conversion and 54.68% of selectivity to e-caprolactam. This discovery establishes a potential method for one-pot synthesis of e-caprolactam from cyclohexane. It may be of potential application prospect and of prominent theoretical significance. Amorphous SiO2–Al2O3 and its supported Co3O4 catalysts were prepared and characterized. These catalysts were employed to catalyze the reaction of cyclohexane with nitrosyl sulfuric acid in the presence of fuming sulphuric acid. It indicates that Co3O4/SiO2–Al2O3 gave better results with 11.93% of conversion and 54.68% of selectivity to e-caprolactam. This discovery establishes a potential method for one-pot synthesis of e-caprolactam from cyclohexane.