Carbon Materials As Catalyst For Cyclohexane Oxidation To Adipic Acid

As catalysts,carbon materials attract a growing interest due to their: (i) stability, (ii) possibility to control the porosity and surface chemistry and (iii) high specific surface area. Carbon materials show good activity in reactions to replace traditional metal catalysts. Hence, it is important to study the catalysis of carbon materials. In this thesis, carbon materials are studied in the catalytic oxidation of cyclohexane. The structure-property relationship and plausible reaction mechanism of carbon nanotubes (CNTs) in the oxidation of cyclohexane were studied in details.The catalytic activities of various carbon materials in cyclohexane oxidation were compared. The effects of the residual of Fe, oxygenous groups and the surface defects on the catalytic properties of CNTs were studied. The results show that the surface defects of CNTs play an important role. It was concluded that the intact graphite sheet structure of CNTs with high electron mobility favors to the oxidation. Based on the insight, N-doped CNTs were used to enhance the activity in the oxidation reaction via changing the electricity of CNTs.The cyclohexane oxidation catalyzed by CNTs is a radical reaction with initiation as a rate determining step. It was proposed that the role of CNTs is either to accelerate the hydroperoxide decomposition or to activate the cyclohexane and O2. CNTs can be recycled without deactivation after filtrating and washing.