Hydroxylation Of Benzene, Phenol And Oxidation Of Pyridine Over TS-1

Titanium silicalite-1 (TS-1), first synthesized by Enichem in Italy in 1983, has been paid much attention because of its excellent catalytic and oxidative performance with H2O2 under the mild reaction conditions. The TS-1/ H2O2 reaction system overcomes the shortcomings of serious pollutions and unsafe factors of traditional oxidative ones, providing new routes for the green chemical engineering and environmental friendly processes. However, the high cost and low reproducibility of TS-1 are still the hurdle for its widely industrial applications. Although many improvements had been made to decrease the synthetic cost and enhance the preparation reproducibility of TS-1 in the past twenty years, more works have to be done to further decrease the cost of TS-1.In this thesis, low cost TS-1 was successfully synthesized by using the Dry Gel Conversion (DGC) method. Triethanolamine was used instead of expensive TPAOH in the preparation of dry gels, and only small amount of TPAOH was needed to impregnate the dry gels, so that TPAOH can be used in high efficiency. TS-1 samples were characterized by XRD, SEM and N2 adsorption.Thereafter, TS-1 synthesized by DGC method was used as catalyst in the hydroxylation of benzene, phenol and oxidation of pyridine, respectively, with H2O2 as oxidizer. Various parameters, such as the influence of solvents, catalyst amount, the amount of H2O2, reaction temperature, and reaction time on conversion and selectivity were investigated. Optimal reaction conditions were obtained from the experimental results.In the hydroxylation of benzene, the conversion of benzene and the effective use ratio of H2O2 were increased with the increasing amount of TS-1, while the selectivity of phenol kept almost constant. The optimal conditions were found to be as follows: the suitable solvent was sulfolane; the initial concentration of benzene was 20% (the mass ratio of sulfolane/benzene=4:1); the mass ratio of TS-1/benzene was 1:10 and...