Simulation And Experimental Study On Separation Of Tetrahydrofuran-toluene-fluorobenzene-water Mixed Solution

Tetrahydrofuran,toluene and fluobenzene are important raw materials in the pharmaceutical and chemical industries.So there are large amounts of mixture aqueous of tetrahydrofuran,toluene,and fluorobenzene are formed.Unfortunately,the mixture solution displays markedly a non-ideal behavior,forming binary and ternary azeotropes,it is hard to achieve separation by ordinary distillation.Based on many literatures home and abroad,the properties,uses and production processes of tetrahydrofuran,toluene and fluorobenzene were summarized,and the separation processes of tetrahydrofuran,toluene and fluorobenzene were generalized systematically.A method of extractive distillation-ordinary distillation was proposed in the paper,using dimethyl sulfoxide and dioctyl phthalate as the solvents.The isobaric vapor-liquid equilibrium date for the quaternary mixtures of tetrahydrofuran-toluene-fluorobenzene-water,the ternary mixtures of tetrahydrofuran-toluene-water and tetrahydrofuran-fluorobenzene-water,the binary mixtures of tetrahydrofuran-toluene,tetrahydrofuran-fluorobenzene,tetrahydrofuran-water and toluene-fluorobenzene have been investigated at normal pressure by means of a dynamic method using a single-cycle vapor-liquid kettle.The software of Aspen plus was used to simulate single-stage extraction and determine the appropriate extraction agent.Then,the optimal extraction agent was determined by single-stage vapor-liquid equilibrium experiment,which provided the basis for ftuther extraction-distillation simulation.Extraction-distillation process was simulated by using Aspen plus software.The references effecting of reflux ratio,quantity of distillation,solvent ratio,theoretical number and material position on extraction-distillation simulation.The orthogonal experiment was designed to optimize the condition of extraction-distillation process.Simulation results showed that the purity and yield of tetrahydrofuran were up to 99.99%and 99.85%,the purity and yield of toluene were up to 99.96%and 97.60%,and the purity and yield of fluorobenzene were up to 99.70%and 99.70%under the optimized conditions.The simulation results provided theoretical basis for the further experiment.Multifunctional extractive distillation apparatus and common distillation column were used for experimental verification on the basis of simulation calculation.The results indicated that the relative error between experimental results and simulation results under the optimal condition is less than 5%.The purity and yield of tetrahydrofuran were up to 99.60%and 97.15%,the purity and yield of toluene were up to 99.54%and 95.83%,the purity and yield of fluorobenzene were up to 99.16%and 96.08%,the purity and yield of dimethyl sulfoxide were up to 99.81%and 99.65%,and the purity and yield of dioctyl phthalate were up to 99.92%and 99.80%.The quaternary mixtures of tetrahydrofuran-toluene-fluorobenzene-water can be separated by using extraction-distillation in this paper.The result of this work will be provided for the further study.