Preparation Of Znic Oxide Supported Metalloporphyrins With Carboxyl Or Polyfluorine Substituents, And Study On Their Catalytic Performance

Metal loporphyrins acted as an artificial model of cytochrome P-450enzyme, has been widely used for high selectively catalysis for aerobic oxidation of alkanes. However, the metal loporphyrins used in homogenous catalysis system are usually oxidized by various oxidants and then can be hardly recovered and further reused. Therefore, a series of supported metal loporphyrins has gradually become hot topics for the researchers in bio-mimetic catalyst. The main contents of this thesis are as follow:1. A development of the catalytic oxidation of toluene/cyclohexane over metal loporphyrins and the supported mentalloporphyrins in modern industry is briefly introduced.2. TCPP Me/ZnO and TPFPP Fe/ZnO, the catalyst material were synthesized and prepared according to the methods in references. A quantitative analysis fundamental and method for the products obtained from oxidation of toluene/cyclohexane over the catalyst material, and an evaluation to catalytic performance of the catalyst material are introduced.3. Zinc oxide supported metalloporphyrins were characterized by UV-Vis, FT-IR, XRD, TG, TEM and EPR techniques and so on. The structure and characteristics of the supported catalysts are investigated and concluded by characterizing their structure and analyzing the experimental data.4. The effects of various factors, i.e. reaction temperature, air pressure, reaction time and amount of metalloporphyrin, on cyclohexane or toluene oxidation over TCPP Me/ZnO were investigated. The catalytic performance and reusability for the supported catalysts for oxidation toluene were researched and discussed under the optimal reaction conditions. And then, the experimental results from toluene and cyclohexane oxidation over TCPP Me/ZnO and TPFPP Fe/ZnO respectively are compared with those over the corresponding unsupported. We also give an evaluation for the catalytic performance of TCPP Me/ZnO.5. By investigating and analyzing some related literatures based on our experiment data, the hypothetic mechanism of the toluene or cyclohexane oxidation catalyzed by ZnO supported metalloporphyrins is offered and originally deduced to be a free radical reaction process. The research results show that, compared with the unsupported manganese porphyrin, the catalytic performance of ZnO supported catalyst with1.5mg TCPP Mn for the toluene oxidation remarkably increased under optimal reaction conditions. The supported catalyst can be reused for10recycles for the oxidation and it gave about, on average,7.5%toluene conversion,51.1%selectivity for alcohol and aldehyde and3.8%yield of benzylalcohol and benzaldehyde.The TPFPP Fe/ZnO catalyst shows a more excellent performance than the unsupported, a quantity of catalyst containing only1.0mg TPFPP Fe supported on ZnO can be reused10times for the oxidation of cyclohexane, on average, with31.8%cyclohexane conversion, and60.0%selectivity to ketone and alcohol, under the better reaction conditions. All above experiment results can prove that ZnO support is very wonderful for the researched metal loporphyrins.