Electrochemical Catalytic Oxidation Of Toluene With Methanol Coupling Reaction

As a typical replaced aromatic hydrocarbon,the selective oxidation of toluene is an important model reaction in the research area of hydrocarbon selective oxidation.So this research not only has an important science meaning but also deep applicative background.Methanol is a main production of coal and petroleum industry,although it was applied broadly in petrochemical and fine chemical productions,,the situation of the providing more the need have been formed currently,affecting the development of industrial chemistry.Therefore,we prepared a series of solid superacid catalysts and researched the coupling reaction of toluene with methanol assisted by the electrochemical synthesis at room temperature and atmospheric pressure.The novel methanol derivative production-methoxymethyl benzene have been developed,it structure is similar to MTBE,not only it have high octane number itself,but also can raise the mark number of the gasoline significantly.It can also as a emulsifier and increase the content of methanol in the gasoline,economizing and substituting the limited petroleum resources.In Additional,this research on the oxidation of aromatic hydrocarbon can also exploit new foreground,carry out the catalytic oxidation of aromatic hydrocarbon at high temperature and pressure more economy energy and more environmental protection.In the first part of the dissertation,the basic knowledge of methanol market,toluene oxidation technology,the clear electrochemical organic synthesis technology and the solid superacid were introduced and reviewed.It simply analyzed methanol market,and highlight introduce the research advance of catalytic oxidation of toluene,including the toluene oxidation production,the toluene catalytic oxidation in liquid phase,the toluene catalytic oxidation in gas phase and the toluene catalytic oxidation in electrolysis.the current development and characteristic of the electrochemistry organic synthesis and the electrosynthesis of aromatic hydrocarbon compound were emphasized.In additional,the basic knowledge of solid superacid can also be expatiated seriously,including the style of acid point,the surface structure,the possible reason of acidic center and the preparation method.Based on the understanding of the electrochemistry organic synthesis and the current development,the second and the third section successfully accomplished the electrochemistry research for the coupling reaction of toluene with methanol catalyzed by different solid superacids. Toluene oxidation was carried out in fluid phase by using electrochemistry and the different metal modified solid superacids,the different solid superacid,composite solid superacids,solid polyoxometalate and ionic liquid as catalyst at the fixed bed reactor and the slurry bed reactor, respectively.The electrolysis time,the content of modified materials and the metal salt types in catalyst were investigated.The ultraviolet spectrophotometer was adopted to track the course of the reactions convenient for controlling.The fourier transform infrared spectrometer(IR),powder X-ray diffraction(XRD),scanning electron microscopy(SEM) and X-ray photoelectron spectroscopy(XPS) had been introduced to characterize catalysts for understanding the metal valence changes,and enriching the experiment data.Gas chromatography/mass spectrometry (GC/MS) were employed to test the final product to give the concentration and structure information, and it can be conclude from the analyses that the effects of the molybdenum modified solid superacid catalysts were better than the other metal modified solid superacid catalysts,the SO₄^2-/ZrO₂ catalyst was better than the other solid superacid catalysts and the solid polyoxometalate catalysts were better than the solid superacid catalysts The reaction mechanisms were conclude by combining the catalytic result,GC/MS data and the literature.In the fourth part of the thesis,the products were determined by gasoline octane number testing instrument to primary evaluate the potential application of the products.In this dissertation,the reaearch of the coupling reaction for toluene with methanol was successfully achieved by using electrochemistry and a series of transition metal modified solid superacid,composite solid superacids,solid polyoxometalate and ionic liquid as catalyst.Moreover, there was no report in literature about using this method.The synthesis process conducted in our research was simple and the reaction conditions were relatively mild.The two reactions can be performed at room temperature with mild conditions and this avoided the high pressure and temperature,and the operations were therefore more convenient and safety.And the synthesis processes were of price-cut,no organic solvent and no pollution.The main product-methoxymethyl benzene may have good prospects of development and application as the gasoline additives,making the new approach for the development and using of methanol derivative.