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Ethanol is one kind of important chemical raw materials and used widely in various industry fields.Due to the presence of a binary ethanol-water azeotrope (95 wt % ethanol),it is impossible to enrich ethanol with a purity of 100% by using a conventionally distillation column.To overcome the problem,this work proposes a new process whereby water in a near-azeotropic ethanol-water mixture is reacted with ethylene oxide (EO) in a reactive distillation (RD) column to form ethylene glycol(EG),diethylene glycol(DEG).The main objective of this research is to investigate the feasibility and to identify suitable design parameters for the proposed process by means of Aspen Plus simulation package.Firstly,the basic characteristics of the chemical systems such as the physical parameters,the phase equilibrium thermodynamics and the reaction kinetics are analyzed in details.The results show that the reaction conditions of EO hydration can meet the basic conditions of the general RD process and therefore the removal of water from a near-azeotropic ethanol-water mixture is possible in a RD column.Secondly,sensitivity analysis is carried out to investigate the influence of the key design parameters (pressure,reflux ratio,feed ratio,feed and reaction stage location) on the process performance (conversion,selectivity,separation efficiency).The results shows that the most important factors affecting water conversion and EG selectivity.Based on these,a suitable RD configuration and some basic design parameters are obtained by the optimization of operating variables.The results found that with the selected design conditions,i.e.,operating pressure 0.5MPa,the mole ratio of the ethylene oxide to water 2/1,reflux ratio 8,the number of stages 25,the key component water could be converted completely in RD column,the ethanol is obtained directly from the distillate of the RD column,and a mixture of by-products including ethylene glycol,diethylene glycol and ethylene glycol monomethyl ether with a molar fraction of 0.7:0.2:0.1 is obtained from the bottom products of column.In addition,the heat released by exothermic reaction can be directly utilized by ethanol distillation.From the simulation results,it is concluded that the RD process proposed in this work offers potential advantages of reduced energy consumption and reduced capital cost over the traditional approaches for the removal of water from ethanol.