Research, To. Condensation Of Formaldehyde And Methyl Formate Methyl Glycolate And Methyl Methoxy-b

Formaldehyde and methyl formate are fundamental raw materials in Cl chemical technology as many kinds of chemicals can be produced from them. From the condensation of formaldehyde and methyl formate, methyl glycolate and methyl methoxy acetate can be synthesized efficiently, and both of them can be used for producing ethylene glycol, this way is of great importance. Condensation of formaldehyde and methyl formate to methyl glycolate and methyl methoxy acetate is studied in this paper. The the influence of binary-catalyst-system - which is the mixture of heteropoly acid and liquid acid, to condensation is discussed, and proper reaction conditions of this react are gotten. The quantity test method of the product and relative theory are also given.Silicotungstic acid mixed with liquid acid to catalize the condensation is mainly studied. Reaction conditions such as the catalyst ratio, reaction temperature, molar ratio of FA and MF and the reaction time are influenced the ratio and selectivity of product to a certain extent. It is found that add proper amount liquid acid can increase the yield of MG and MMA. Among those liquid acid, sulfric acid showed the greatest influence on the yield. Just add 30% sulfric acid can increase the yield of MG and MMA to 6.35% and 11.57% respectively. sulfric acid can stimulate the decompose of MF and cut the time of pressure increasing from 98min to 72min. Add polyphosphoric acid or methanesulfonic acid can also increase the yield of MG and MMA. But contrast to sulfric acid the influence are relative weak. The experiment also indicate that after adding liquid acid reaction temperature decreased slightly, the yield increased while rising molar ratio of FA and MF, and reaction time could be controlled under 3-4 h.The method of methanol treated reaction moist analysed by using the Gas Chromatograph is build in this paper, which can carry out quantity and qualitaty test. Under stable condiction, methanol treated reaction moist is qualitative analysized by compared with the retention time of pure samples. Based on the concentration range of methanol treated reaction moist, the standard mixture is confected. In the consequence, the concentration emendate equations for MG andMMA are set up. They are y =5. 9267 ln x + 1.4406 for MG and y -8.2344 Inx-5.5652 for MMA. The relative error of both equation is less than 2%. By using these two equations, the conent is calculated.The reaction mechanism of binary-catalyst-system is explored also. Compared single-catalyst-system and binary-catalyst-system, heteropoly acid mainly act under the effect of acid-base synergistic. The anions of heteropoly acid can stabilize the intermediate. Liquid acid can benfit to the contact of heteropoly acid and react gas. H+ given by sulfric acid acted with =O, stabilized MG in the gas phrase.