溶剂对环氧乙烷催化水合制乙二醇的影响

研究了NY催化剂催化环氧乙烷水合制乙二醇(EG)过程中,溶剂、催化剂添加量和水与环氧乙烷的摩尔比(简称水比)对EG选择性的影响。实验结果表明,以丙三醇作为溶剂使催化剂进行循环,能提高EG的选择性,效果好于以生成的EG作为溶剂循环催化剂。催化剂添加量、水比和溶剂添加量对EG选择性具有较大影响,其中溶剂添加量对EG选择性的影响最显著。在低水比(1.0~4.0)条件下,EG质量分数小于30%、催化剂质量分数大于7.2%时,EG选择性稳定在95.63%~97.92%,平均值为96.80%,此结果对于进一步降低EG合成工艺的能耗具有指导意义。

Effect of Solvent on Synthesis of Ethylene Glycol by Ethylene Oxide Hydration

Synthesis of ethylene glycol(EG)from ethylene oxide(EO)by catalytic hydration was studied.Effect of solvent,catalyst dosage and n(H_2O) ∶n(EO)on selectivity of EG were investigated.Choosing glycerol as solvent to recycle catalyst can raise selectivity of EG.Catalyst dosage,n(H_2O) ∶n(EO)and solvent dosage can affect selectivity of EG.The major factor is solvent dosage.When NY used as catalyst,glycerol as solvent,n(H_2O) ∶n(EO)1.0-4.0,mass fraction of EG less than 30% and mass fraction of catalyst more than 7.2%,selectivity of EG can reach 95.63%-97.92%.The result is important in reducing energy consumption of the process.