Methane Oxidation To Esterification Of The Methyl Acetate Synthesis Process

Series of solvent systems were reviewed in this paper in accordance with the reaction system on the liquid part of the catalytic oxidation of methane in domestic and foreign research. Finally, the ways of the preparing for methyl acetate were reviewed too.This paper analyzed the characteristic of the methane partial oxidation reaction in the fuming sulfuric acid solvent system, proposed the new method of oxidative esterification of methane to methyl acetate in the mixing solvent of acetic acid. The main work included: developing the system of synthesis of methylacetate in the mixed HAc solvent system; measuring the acidity of the mixed reagent and recognizing the relationship between the acidity of the mixed reagent and the conversion of the methane; selecting optimum acetic acid mixed reagent system for higher methane conversion and studying its process conditions and its kinetics.First, the oxidation of methane over the fuming sulfuric acid system was analyzed. According to the theory of the reaction over the fuming sulfuric acid, the oxidative esterification of methane to methyl acetate over the mix acetic acid reagent was proposed. By adding strong acid, the acetic acid solution could improve the acidity. The I2 and KMnO4 for the synthesis of methyl acetate in the mixing of acetic acid were selected as a catalyst and oxidant. The experiment proved the system's optimum conditions over the mixture of HPWMoA and acetic acid:concentration of I2 0.04 mol/L, concentration of KMnO40.20 mol/L, the temperature was 210℃, pressure was 4 MPa, conversion rate of methane could reach 27.7%, and selectivity could rise up to 96%. Second, the acidity of the mixing of was the acetic acid determined by acid-base titration, Hammett-UV spectrophotometer. It was proved that acid-base titration could only determined colorless mixture of acetic acid reagent; Hammett-UV spectrophotometer using methyl violet, solvent using chloroform, optimum conditions:indicator concentration of 5.4 x 10-3mmol/L, concentration of acetic acid mixture reagents of 58 mmol/L. And association analysis between oxidative esterification of methane to methyl acetate and the acidity of the acetic acid were made. Finally, the kinetics of oxidative esterification of methane to methyl acetate over the mixture of HPWMoA and acetic acid were studied. It showed that oxidative esterification of methane to methyl acetate in the mixture of HPWMoA and acetic acid was 0.5 level reacetion.