Highly efficient cobalt-doped carbon nitride polymers for solvent-free selective oxidation of cyclohexane

Constructing Defective Co3V2O8 Hexagonal Prism for Solvent-free Selective Oxidation of Cyclohexane: Strategy of Ionic Liquid Mediation

“…A typical example is that of the selective oxidation of cyclohexane to KA oil, in which the corresponding products are the crucial intermediates for the nylon manufacturing industry. 1,2 To obtain a higher KA oil selectivity (>80%) in the traditional industry, the cyclohexane conversion was commonly limited to approximately 5% to reduce the formation of excessive oxidation byproducts. 3 Therefore, many research contributions have been devoted to overcoming the trade-off effect between activity and selectivity in the aerobic oxidation of cyclohexane, such as mixed metal oxides (MMOs), carbon materials, zeolite-based catalysts, porphyrinic compounds, and metal−organic framework-based catalysts.…”

Roles of Oxygen Vacancies in CeO2 Nanostructures for Catalytic Aerobic Cyclohexane Oxidation

“…The reaction pathway of cyclohexane oxidation was generally revealed through investigating the conversion and selectivity under different reaction times, as displayed in Figure (a,b), respectively. The oxidation process mainly consists of two parts: the oxidation for cyclohexane to KA oil and the further oxidation from KA oil to adipic acid, matching the widely accepted cyclohexane oxidation mechanism. − The conversion–time curves in Figure (a) suggested an increasing trend for the conversion, and a noticeable feature is that NCe-{100} performed the fastest oxidative induction period. As for the selectivity–time curves in Figure (b), at the beginning of the oxidation period (0–1 h), the main transition was cyclohexane to KA oil, and as the oxidation period progresses (1–2 h), the transition of KA oil to adipic acid started to be noticed.…”

“…The oxidation of hydrocarbons into value-added chemical products, especially alkanes that are much more difficult to utilize without active functional groups, is of great importance in the chemical industry. − Cyclohexane oxidation is a typical hydrocarbon resource high-value utilization process, and in this process, the oxidation products including cyclohexanol, cyclohexanone (referred to as KA oil), and adipic acid are important organic intermediates for nylon-6 and nylon-66 in the nylon industry. ,− For the details of cyclohexane oxidation, the widely accepted oxidation process of cyclohexane includes the activation of cyclohexane to a cyclohexyl radical, the transition to KA oil, the further oxidation to adipic acid, and the over oxidation to glutaric acid, succinic acid, and other byproducts, as described in Scheme (b). − As a complex radical oxidation reaction, it is a great challenge to activate the C–H bond and to generate active radicals under proper conditions due to the strong and inert C–H bonds, and on the other hand, it is also an important issue to investigate in order to control the oxidation process to realize the production of target products under high selectivity and avoid over oxidations. − …”

Visible Light-Driven Sandwich-like g-C3N4-Catalyzed Oxidation to Produce Cumene Hydroperoxide

“…The structural properties of the catalysts were investigated using X-ray diffraction (XRD), and the results are shown in Figure a. The seven as-synthesized g-C 3 N 4 catalysts exhibited similar crystal structures, with two notable diffraction peaks at 2θ = 12.9 and 27.7°, which corresponded to the (100) and (002) crystal planes of g-C 3 N 4 , respectively. , The diffraction peak observed at 12.9° was attributed to the in-plane triazine ring structure stacking, and the crystal plane distance of this peak was approximately 0.686 nm. The diffraction peak observed at 27.7° exhibited a higher peak intensity, which could be attributed to the interlayer stacking of the conjugated system, and the crystal plane distance of this peak was approximately 0.322 nm.…”