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Abstract Efficient Early Stage Chemical Process ABSTRACT EFFICIENT EARLY STAGE CHEMICAL PROCESS DESIGN by Pratik Dhakal Design of any chemical processes on a large scale such as distillation, extraction requires tremendous amount of data. Such data can be obtained either through literature review (if available), experiments, molecular, property prediction tools. Conducting experiments on a large scale for multicomponent mixtures at different variables can be quite expensive and time consuming, while molecular simulation is still computationally demanding even though it can provide accurate molecular level details. Property prediction tools are simple analytical model based on empirical relations or thermodynamics relations that can provide accurate estimates, which is why they are used throughout the industry. However, most commons property predictions tools provide no qualitative insight on a molecular level that could be extremely useful for process intensifications. Thus, this research is focused on a analytical model called MOSCED that has shown tremendous capability in providing accurate property predictions and qualitative molecular insights that could guide chemical process design during early stage. EFFICIENT EARLY STAGE CHEMICAL PROCESS DESIGN Thesis Submitted to the Faculty of Miami University in partial fulfillment of the requirements for the degree of Master of Science by Pratik Dhakal Miami University Oxford, Ohio 2018 Advisor: Dr.Andrew Paluch Reader: Catherine Almquist Reader: Dr Shashi Lalvani ©2018 Pratik Dhakal This thesis titled EFFICIENT EARLY STAGE CHEMICAL PROCESS DESIGN by Pratik Dhakal has been approved for publication by The College of Engineering and Computing and Department of Chemical, Paper and Biomedical Engineering ____________________________________________________ Dr. Andrew Paluch ______________________________________________________ Dr. Catherine Almquist _______________________________________________________ Dr. Shashi Lalvani Contents 1.Introduction .................................................................................................................................................................. 1 1.1 Motivation ........................................................................................................................................................... 1 1.2. Background ........................................................................................................................................................ 2 2. Application of MOSCED to Predict Limiting Activity Coefficients, Hydration Free Energies, Henry’s Constants, Octanol/Water Partition Coefficients, and Isobaric Azeotropic Vapor-Liquid Equilibrium ...................................................................................................................................................................... 6 2.1 Introduction .......................................................................................................................................................... 6 2.2 Computational Methods ................................................................................................................................... 6 Solvation Free Energy .............................................................................................................................................. 6 Henry’s Constant ....................................................................................................................................................... 7 Partition Coefficient .................................................................................................................................................. 8 Binary Vapor-Liquid Equilibrium ..................................................................................................................... 9 2.3 Result and Discussions. ............................................................................................................................... 12 Association/hydrogen bonding term ................................................................................................................. 12 Limiting Activity Coefficient, Solvation Free Energy, and Henry’s Constant .................................... 16 Partition Coefficients ............................................................................................................................................. 23 Azeotropic vapor/liquid equilibrium................................................................................................................. 25 3.4 Conclusion ........................................................................................................................................................ 32 2.5 References ........................................................................................................................................................ 34 3.Expansion of MOSCED using new UNIFAC based Group Contribution Method and Linear Solvation Energy Relationship (LSER). Application: Predicting Activity Coefficient at Infinite Dilution for Non-Hydrogen Bonding Molecules ............................................................................................... 41 3.1 Introduction. ................................................................................................................................................... 41 3.2 LSER correlation: ........................................................................................................................................... 42 3.3 Correlating LSER parameters with MOSCED. ..................................................................................... 43 Data Collection ........................................................................................................................................................ 44 Correlation: ............................................................................................................................................................... 44 UNIFAC based Group Contribution Method: ................................................................................................ 45 3.4 Result and Discussions. ............................................................................................................................... 47 Application: .............................................................................................................................................................. 52 3.5 Conclusion: ....................................................................................................................................................... 55 iii 3.6 References: ....................................................................................................................................................... 55 4. Expansion of MOSCED to Ionic Liquids for Efficient Early Stage Chemical Process Design: Application such as selecting Entrainers, breaking Azeotropic Vapor Liquid Equilibria ..................... 58 4.1 Introduction .................................................................................................................................................... 58 4.2 Methodology .................................................................................................................................................... 61 Data Collection ........................................................................................................................................................ 61 Regression ................................................................................................................................................................ 62 Quantifying Errors ................................................................................................................................................. 63 4.3 Computational Methods ................................................................................................................................ 63 Ternary Vapor-Liquid Equilibrium Modelling .............................................................................................. 63 Selectivity Coefficient and Distribution Coefficient ................................................................................ 65 4.4 Result and Discussion .................................................................................................................................. 66 MOSCED Parameters ........................................................................................................................................... 66 Ternary Vapor Liquid Equilibrium Result ...................................................................................................... 74 Selectivity ................................................................................................................................................................. 79 4.5 Conclusion ........................................................................................................................................................ 81 4.6 References: ....................................................................................................................................................... 81 iv List of Tables 11 Table 1: MOSCED association parameters for chloroform, acetone, methanol, and N- 1/2 3 1/2 methylpyrrolidone, where αi and βi have units of MPa or (J/cm ) . ................................................. 12 Table
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