Design And Study Heterogeneous Catalysts For Selective Qxidation Of Cyclohexane

Cyclohexanone and cyclohexanol (K/A oil) are important materials of many industrial products, which play a key role in daily life and manufacturing industry. The conversion of cyclohexane is controlled at ～4% in industry, and the selectivity of K/A oil is 75～85% in industry. How to improve the cyclohexane conversion and keep the high selectivity of K/A oil, it continues to be a great challenge for cyclohexane oxidation in catalysis.In present work, the different kinds of catalysts were designed and synthesized by different method, including AuNPs catalysts, molecular sieve catalysts and bi-component metals catalysts. The catalytic performance of all catalysts is good in the selectivity oxidation of cyclohexane with molecular oxygen. Especially, the catalytic performance of bi-component metals catalysts is excellent.The AuNPs catalysts were synthesized by using the modified mesoporous SBA-15 with different silane coupling agents. The parameters and catalytic performance of all catalysts were characterized by a series of Characterization methods. The results indicated that the dispersion and size of AuNPs catalysts synthesized were good and uniform. The activity of the 1.000Au-SBA-S4-cal catalyst is best in all samples, which conversion of cyclohexane is 10.9% and the selectivity of K/A oil is 84.2%.The catalytic performance of molecular sieve catalysts was characterized by many methods. The result showed the catalytic activity of 1%Co-SBA-15 catalyst was better in all catalysts, the cyclohexane conversion is 10.2% and the selectivity of K/A oil is 80.3%.It was studied that the Mg was incorporated in Cu species catalysts. The results indicated the bi-component catalysts had an excellent catalytic performance in cyclohexane oxidation. The best conversion of cyclohexane is 12.0% and selectivity is 99.3%. Moreover, the activity of catalysts with different amount of incorporating Mg was discussed. The results showed the activity of catalysts increased with the increase of magnesium loading within limits. In addition, the optimum technological conditions of selectivity oxidation of cyclohexane were studied with 1.2Mg-2.3Cu/SBA-15 catalyst, the best optimum technological conditions:time for 70min, oxygen pressure for 1MPa, temperature for 423 K.Recycling test with the catalyst 1.2Mg-2.3Cu/SBA-15 was measured by cyclohexane oxidation reaction. The catalyst remained a good activity even after four times recovery, showing the good stability of this catalyst.