The Synthsis Of 2-ethoxyethanol In Membrane Reactor

Ethylene glycol ether is one of the ramifications in epoxy compounds.Because of the existence of hydrophilic groups such as hydroxyl and ether group and hydrophobic alkyl groups,they have nice decontamination for water-solubility and oil-solubility dirt.They are excellent industrial solvents,so they are widely used in dope,printing,dyes and cleaning.2-ethoxyethanol is the representative product in ethylene glycol ethers.It is widely used as solvent of nitration cellulose,man-made resin and paints;it is used as colorant in leather and in dope and textile industry.In addition,it is used to produce acetate ester;therefore,it is very import to research it.By using ethanol and ethylene oxide(EO)as materials,2-ethoxyethanol was produced in membrane reactors.The catalysts' performance and reaction conditions are investigated.The whole contents are as following:By using 5A molecular sieve as carrier,KOH was loaded on it by equivalent volume and seven kinds of catalysts were prepared with 2%to 31.2%loading of KOH which were used in the ethoxylation.MgO/Al₂O₃ composite catalyst was prepared by coprecipitation method and the modified composite oxides were prepared by adding the third metal ion.Catalysts are characterized by BET,XRD and FT-IR.Catalytic performance was researched in ethoxylation between ethanol and EO.Ethoxylation was present in membrane reactor.Reaction temperature,space velocity and catalyst amount were investigated and the optimum reaction condition of different catalysts were got:under the condition at 110℃,1h^-1and 2g 17.6wt%KOH/5A molecular sieve,the selectivity of 2-ethoxyethanol reached 88.81%;under the condition at 110℃,1h^-1and 2g MgO/Al₂O₃ composite catalyst,the selectivity of 2-ethoxyethanol reached 82.96%;under the condition at 110℃,1h^-1and 1.5g modified MgO/Al₂O₃ composite catalyst,the selectivity of 2-ethoxyethanol reached 91.56%.Catalysts life was researched in the paper.Because of the product separated from catalyst,the catalysts can be utilized repeat many times and their catalytic activities were not changed.By using KOH/5A molecular sieve and MgO/Al₂O₃ compound as catalysts,the ethoxylation were present in membrane reactor and batch reactor.It was show that the selectivity on 2-ethoxyethanol in membrane reactor is higher than in batch reactor.