Research On Synthesis Of Methyl Acrylate Over Acid-base Bifunctional Catalysts

Acrylic esters are widely used in organic synthesis because of its excellent properties. Acrylic esters are mainly used in chemical fiber, textile, leather, paints, adhesives and super absorbent resin, and its development and application of downstream products, making the growing demand for acrylic esters. Acrylic esters are high value-added chemicals, major domestic and foreign chemical companies have also increased the production of acrylic ester. Therefore, the synthesis of acrylic esters has also become a hot topic.At present, the production methods of acrylic esters mainly include reppe method, propylene oxidation, propane oxidation, methyl and formaldehyde method. The industrial production of acrylic esters are mainly propylene oxidation. This method has become more mature with the industrialization of the application gradually, but the process itself also exists a lot of deficiencies. Therefore, in recent years there have been many new synthesis methods, which include acetate formaldehyde method. The catalysts of acetate formaldehyde method to synthesis acrylic esters use solid base catalyst, while in recent years acid-base bifunctional catalysts appear for this reaction, and have got a great improvement.This paper used methyl and formaldehyde to synthesize methyl acrylate, A basic metal oxide was loaded on the catalyst and Al2O3 as a support, in the early adding additives to improve the performance of the catalyst channel. And acid-base bifunctional catalyst was prepared by adding a modified product. Synthesis conditions were discussed in the process of catalysts preparation, and catalysts were characterized by SEM, physical adsorption, TPD and so on.The catalysts were synthesized by adding loaded with active material additives and then at a certain temperature calcined to form porous catalysts having good permeability performance. The different types of basic metal oxides were loaded to find out having a high activity active sites as well as the proportion of optimal load, and the reaction performance and optimal reaction conditions of acetate and methylal synthesizing methyl acrylate were initially studied, at a temperature of 385 ℃, space velocity of 1.5h-1, the ester aldehyde ratio of 2:1 selectivity of the reaction can reach 56.76%; Different metal oxides were added on the basis of the previous step on the catalysts to be modified. The optimal metal oxide modified product was selected, and different acid-base proportion was adjusted. Best acid-base balance of the catalyst was studied. Reaction performance and optimal reaction conditions were determined, At a temperature of 390 ℃, space velocity of 3.0h-1, the ester aldehyde ratio of 3:1 selectivity of the reaction can reach 60.16%.