Study On The Catalysis Of Metal Tetrakis (P-Carboxyl Phenyl) Porphyrin Immobilized On Lead Sulfide For Ethylbenzene Oxidation

We used lead sulfide as support coordinatingmetal tetrakis(p-carboxylphenyl)porphyrins to mimic the regulating function to catalysis of Cytochrome P-450 enzyme via cysteine,and to study on how the supported catalysts did their catalysis for oxidation of ethylbenzene with O2.According to references review and the experimentaldata about catalytic ethylbenzene oxidation,ethylbezene oxidation mechanism over the supported catalystsis discussed.The contents for this work are as follows:1.A research progresse for the preparation and application of supported metalloporphyrins,and the catalytic oxidation technology forethylbenzene is summarized.2.Metal tetrakis(p-carboxyl phenyl)porphyrin(MTCPP),lead sulfide(PbS)and lead sulfide-immobilized metal tetrakis(p-carboxyl phenyl)porphyrin(MTCPP/PbS)are prepared based on some references.3.The physical structure and chemical characteristics about the catalyst materials were analyzed and studied via a variety of characterization methods,such as Ultraviolet-visible spectroscopy(UV-Vis),Fourier transform infrared spectroscopy(FT-IR),Scanning electron microscope(SEM),Specific area Test(BET),Thermo-gravimetric analysis(TG-DTA)and X-ray photoelectron spectroscopy spectra(XPS).4.The optimum reaction conditions for ethylbenzene oxidation over MTCPP/PbS were explored and determined in single factor variable method.Subsequently,the catalytic performances of immobilized catalyst materials reused in the optimum reaction conditions were also researched,and compared with those from MTCPP.5.The experimental data show that the catalytic activities of MTCPP were improved by lead sulfide.The yields of ketone and alcohol in ethylbenzene oxidation over Fe TCPP(Cl)/PbS,Mn TCPP(Cl)/PbS and CoTCPP/PbS,in comparision with those obtained from the correspongding M TCPP,increased 7.13%,7.74%and 20.10%,respectively.The catalyst materials can be reused four times for the ethylbenzene oxidation,and the averaged catalytic activity remained higher than those of the corresponding M TCPP.The averaged yields of ketone and alcohol in ethylbenzene oxidation over Fe TCPP(Cl)/PbS,Mn TCPP(Cl)/PbS and Co TCPP/PbS,increased 5.54%,4.25%and 4.51%,respectively.The size order for the catalytic performance isCo TCPP/PbS>MnTCPP(Cl)/PbS>Fe TCPP(Cl)/PbS.6.The effecting factors on catalytic activity in ethylbenzene oxidation,and the reaction mechanism are discussed via referencing the relative literatures,and analyzing the experimental data.