Catalysis Synthesis Of Ethylene Glycol By Ionic Liquids

Ethylene glycol(EG) is a important chemical material, widely used as monomer of polyester and a major component of antifreeze. Simultaneously, It is a kind of material of preparing alkyd, plasticizer, coating, adhesive, surfactant, detonator and electrolyte of capacitor and so on. Now, demand of EG is increasing by year in the world. In2000year,12million ton was needed, in2010year,21million ton will be needed prospectively. Now EG is prepared by three ways:firstly, non-catalytic or catalytic hydration of ethylene oxide (EO); secondly,hydrolyzation of ethylene carbonate that was synthesized with ethylene oxide and carbon dioxide; thirdly, synthesis gas. The first method is a traditional technology for manufacturing for EG, but it’s disadvantages are using a large excess of water and consuming much of energy. Now, the second method have been attracted much of attention about pre preparation of EG. It includes two steps:ethylene carbonate is synthesized by ethylene oxide and carbon dioxide with catalyst; hydroxylation of ethylene carbonate. the ratio of water to ethylene oxide is decreased to1～1.2:1. As a new method, synthesis gas just begin to explore with it’s non-expensive material.In the second method, ionic liquids were as catalysts. according to many of experiments, the conversion of EO is100%, the yield of ethylene carbonate is90%, selectivity of ethylene carbonate is99.7%.