Separation Of(Methyl) Methacrylate Mixtures And System Integration

(Methyl)methacrylate is an important chemical raw material and organic monomer,and is widely used in textile,coating,building and manufacturing industries.High purity(methyl)methacrylate(?99.8 wt%)is highly attractive to commercial application.Removal of trace impurities,such as water,intermediate product methacrolein and methacrylic acid,is the key process to obtain high purity(methyl)methacrylate in industry.This thesis mainly focuses on solving the problems of obtaining high purity(methyl)methacrylate.Thermodynamics,separation method and system integration in the separation system of(methyl)methacrylate were systematically studied in order to solve the difficulty of obtaining high purity(methyl)methacrylate in industry.Main research contents and results were illustrated below:(1)The liquid-liquid and vapor-liquid equilibrium data of methacrolein-water,methacrolein-propanal and methacrolein-methacrylic acid-water were systematically measured.Thermodynamic consistency of the experimental data was evaluated,and the experimental data were correlated and the relevant binary interaction parameters were received using NRTL,UNIQUAC.Reliability of three models in equilibrium calculations has been verified by the error analysis between the simulated and experimental values.Phase equilibrium data of(methyl)acrylate system were improved and a complete thermodynamic system was constructed.(2)The extractant of methacrylic acid was screened and the extraction process of methacrylic acid was designed and developed through the combination of experiment and calculation.The experiments were investigated with toluene,cyclohexane and n-hexane three different extractant candidates to measure liquid-liquid equilibrium data and to establish the effects of extraction temperature and dosage of extractant.The binary interaction parameters for the UNIQUAC model to be used for equilibrium calculations were fine-tuned with measured data.Then,a process for the solvent based extraction of methacrylic acid recovery is designed and verified through simulation with the regressed UNIQUAC model parameters.The optimal configuration of the process flowsheet is determined by minimizing the total annualized cost.The comparison results of economic are:toluene>n-hexane>cyclohexane.Finally,the optimum extraction conditions of toluene were determined using toluene as the solvent.It provided a theoretical foundation for the extraction and separation of methacrylic acid in industry.(3)A systematic separation method for multi-component separation of acrylic acid and methyl acrylate systems was designed.Based on the thermodynamic analysis,a superstructure including several separation feasibility was established,and the search range of separation was reduced.Taking energy consumption as the objective function,the optimal separation process was determined.The separation of an eight-component mixture that includes azeotropes was selected as a case study to highlight the main features of the proposed method.The application results confirm that the method allows a reliable design and synthesis of multicomponent separation systems,and more specifically,for acrylic acid and methyl acrylate.(4)The pilot separation process of methyl methacrylate in 1000 ton scale was verified Based on the data of the pilot-scale experiment,the separation of intermediate product methacrylic acid and product methyl methacrylate was verified by simulation calculation.The design of methyl methacrylate separation process is basically consistent with the pilot-scale experiment,with an error of about 5%.The error between design and experiment is relatively large,which was about 10?15%.