Process Separation Of Ethylene Glycol From The Polyols Mixture

With the global depletion of non-renewable energy, we can use this approach thatdevelopment new energy to open new doors for economic development, theproduction process of biological fermentation liquid separation alcohol alternative tothe process of preparation Chemical alcohol by the increasing depletion of oilresources.we studied in this paper that separation polyols process the from fermentationtreatment liquid, and using the two methods to study the separation process, the firstmethod is using a heterogeneous azeotropic distillation process to separating themixture of ethylene glycol and1,2-Butanediol, The separated experiment conductedseveral times. Because ethylene glycol and1,2-butanediol is a close boiling mixture,and the conventional distillation methods cannot be separated it. So we adopted theheterogeneous azeotropic distillation method to separation the azeotropic distillationmixture and selection EBE as the entrainers, binding the selectivity of entrainer andthe boiling point of the azeotropic to determine which the entrainer is best. Repeatedexperiments demonstrated the conditions of distillation that using EBE as theentrainer, the plate number of the distillation column38,85.3kPa pressure and areflux ratio of10, and we can be well separated the mixture of ethylene glycol and1,2–butanediol. Finally the separation purity of ethylene glycol up to99.7%, therecovery reaches80.32%. Compared with the conventional distillation, using theheterogeneous azeotropic distillation to separate Binary system, increase the relativevolatility of the material and product purity and yield.The second method is to use theextraction and the continuous azeotropic distillation techniques separation glycol and1，2-butanediol mixture. By the ASPEN modeling simulation to using CPO asentrainers, while initially identified the distillation conditions. The whole experimentprocess includes the following steps: a polyols mixture and the extraction entre intothe rectifying column in central by room temperature, CPO and ethylene glycol are obtained on overhead，The tower kettle obtain high concentrations of1,2-butanediol.CPO is a polar solvent, miscible with ethylene glycol to form a homogeneous solution,so the need to add another extraction to separate the new mixture. KD cannotinsoluble in CPO Completely but can be insoluble by ethylene glycol, it was added tothe azeotropic mixture, so that the overhead azeotropes stratification and theentrainers can be recovered. Ethylene glycol solution can be separated by distillation,this method has been very mature. Experiments confirmed: under the distillationconditions，using of CPO as entrainers， the distillation column plate number is66,the operating pressure81.3kpa, operating under a reflux ratio of10, be able to get thebest separation effections, the azeotropes purity reached99.5%.