Research On The Direct Synthesis Of Methyl Acrylate From Methanol And Methyl Acetate

Methyl acrylate, which is a kind of important organic synthesis monomer that has the unsaturated double bond structure, is widely used in the synthesis of polymers and other products. The synthesis of downstream polymers and other substances are widely used in chemical fiber, coating, adhesives, rubber, plastics and other fields. The synthetic methods of acrylic esters mainly consists of propylene oxidation method, acrylonitrile hydrolysis method, acetylene method, propane oxidation method, acrylic acid and methanol esterification method, acetic acid (ester) formaldehyde method. At present, the two step oxidation of propylene production technology is widely used in industry. Due to the depletion of fossil fuel oil. People started to pay attention to the coal chemical products of methanol and its downstream products, such as formaldehyde and methyl acetate etc, and to make full use of coal chemical industry and its downstream products to synthesis essential products. This is a promising research topic. Formaldehyde and methyl acetate gas phase aldol condensation reaction of preparing methyl acrylic acid is a potentially effective way to eliminate dependence on oil production.The synthesis of mlethy acrylate from methyl acetate and methanol was studied. The coupling reaction of methanol to formaldehyde and methyl acetate condensation catalyzed by iron molybdenum catalyst and solid base metal catalyst was studied.Using coprecipitation method synthesis iron molybdenum catalyst with a suitable ratio of Mo and Fe. And preparation of solid base catalyst with Pseudo Bothemite as the precursor, with activated carbor as additives and with Ba and Sr as alkaline active center. The influences of the different active component, load capacity and molding method of the different catalysts were studied with XRD, NH3-TPD and CO2-TPD. The catalysts were analyzed by the fixed bed reactor. The technologic conditions of the reaction was optimized.When the ratio of molybdenum and iron is 2.5-2.8, the excess of Mo forms MoO3, which can prolong the life of the catalyst. Using activated carbon as an additive load of alkaline earth metal oxide, alkaline earth metal was loaded into the activated carbon pore by wet impregnation method, and mixed forming with Pseudo Boehmite, this is conductive to the reaction. The catalysts loaded alkali activity center with Al2O3 as carrier, balanced acidity and basicity of catalyst. Through the comparison of different alkaline earth metal active center, shows that the reaction activity have improved the alkaline earth metal added and the SrO significantly increased the reaction selectivity and the yield.The effect of the mixed molding and the separate molding of iron molybdenum catalyst and solid base catalyst on the reaction was discussed. The effect of large particles of the separate molding mixture is better. After mixed molding and roasted,the interaction between Fe-Mo and Al2O3 or alkali metal oxide can influence on the reaction effect.The suitable process conditions of iron molybdenum catalyst and SrO/Al2O3-BaO catalyst is the molar ratio of methyl acetate and methanol is 1:2, material flow 4ml/h, air velocity was 40ml/min, the reaction temperature is 375 ?, methyl acrylic acid selectivity can reach 40.57%, and the yield is 14.49%.