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Aqueous Hydrocarbon Systems: Experimental Measurements and Quantitative Structure-Property Relationship Modeling

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Aqueous Hydrocarbon Systems: Experimental Measurements and Quantitative Structure-Property Relationship Modeling AQUEOUS HYDROCARBON SYSTEMS: EXPERIMENTAL MEASUREMENTS AND QUANTITATIVE STRUCTURE-PROPERTY RELATIONSHIP MODELING By BRIAN J. NEELY Associate of Science Ricks College Rexburg, Idaho 1985 Bachelor of Science Brigham Young University Provo, Utah 1990 Master of Science Oklahoma State University Stillwater, Oklahoma 1996 Submitted to the Faculty of the Graduate College of the Oklahoma State University in partial fulfillment of the requirements for the Degree of DOCTOR OF PHILOSOPHY May, 2007 AQUEOUS HYDROCARBON SYSTEMS: EXPERIMENTAL MEASUREMENTS AND QUANTITATIVE STRUCTURE-PROPERTY RELATIONSHIP MODELING Dissertation Approved: K. A. M. Gasem DISSERTATION ADVISOR R. L. Robinson, Jr. K. A. High M. T. Hagan A. Gordon Emslie Dean of the Graduate College ii Preface The objectives of the experimental portion of this work were to (a) evaluate and correlate existing mutual hydrocarbon-water LLE data and (b) develop an apparatus, including appropriate operating procedures and sampling and analytical techniques, capable of accurate mutual solubility (LLE) measurements at ambient and elevated temperatures of selected systems. The hydrocarbon-water systems to be studied include benzene-water, toluene-water, and 3-methylpentane-water. The objectives of the modeling portion of this work were to (a) develop a quantitative structure-property relationship (QSPR) for prediction of infinite-dilution activity coefficient values of hydrocarbon-water systems, (b) evaluate the efficacy of QSPR models using multiple linear regression analyses and back propagation neural networks, (c) develop a theory based QSPR model, and (d) evaluate the ability of the model to predict aqueous and hydrocarbon solubilities at multiple temperatures. I wish to thank Dr. K. A. M. Gasem for his support, guidance, and enthusiasm during the course of this work and Dr. R. L. Robinson Jr. for his guidance and editorial skills. I am also thankful for the service of Drs. K. High and M. Hagen on my graduate committee. Discussions with my fellow students, particularly Srini Godavarthy, also provided encouragement and assistance in overcoming obstacles. I gratefully acknowledge the sacrifice and support of my parents in the pursuit of my educational goals. My wife deserves many thanks for her tolerance and iii understanding, and the unconditional love and support I received from my children during this endeavor always resulted in excellent stress alleviation. iv Table of Contents CHAPTER 1. OVERVIEW ............................................................................................ 1 1.1 Rationale ........................................................................................................... 1 1.2 Objectives ......................................................................................................... 2 1.3 Dissertation Organization................................................................................. 2 CHAPTER 2. LITERATURE REVIEW ........................................................................ 4 2.1 Introduction....................................................................................................... 4 2.2 Benzene-Water System..................................................................................... 4 Solubility of Benzene in Water............................................................................... 4 Solubility of Water in Benzene............................................................................... 5 2.3 Toluene – Water System................................................................................... 6 Solubility of Toluene in Water ............................................................................... 6 Solubility of Water in Toluene ............................................................................... 6 2.4 3-Methylpentane – Water System..................................................................... 7 Solubility of 3-Methylpentane in Water ................................................................. 7 Solubility of Water in 3-Methylpentane ................................................................. 7 2.5 Experimental Methods...................................................................................... 7 2.6 Summary........................................................................................................... 9 CHAPTER 3. EXPERIMENTAL APPARATUS......................................................... 10 3.1 Introduction..................................................................................................... 10 3.2 Description...................................................................................................... 11 Feed Section.......................................................................................................... 11 Equilibration Section ............................................................................................ 13 Separation Section ................................................................................................ 13 CHAPTER 4. EXPERIMENTAL METHODS AND TECHNIQUES......................... 16 4.1 Introduction..................................................................................................... 16 4.2 Sample Preparation......................................................................................... 16 Organic Phase ....................................................................................................... 17 Solvent Amount .................................................................................................... 17 4.3 Sample Collection........................................................................................... 19 4.4 Instrument Calibration.................................................................................... 19 4.5 Sample Analysis..............................................................................................26 4.6 Experimental Discussion................................................................................ 26 CHAPTER 5. MUTUAL SOLUBILITIES IN THE BENZENE – WATER, TOLUENE – WATER, AND 3-METHYLPENTANE-WATER SYSTEMS..................................... 29 5.1 Introduction..................................................................................................... 29 5.2 Experimental Measurements........................................................................... 30 Materials ............................................................................................................... 30 v Apparatus .............................................................................................................. 31 Feed Section.......................................................................................................... 32 Equilibration Section ............................................................................................ 32 Separation Section ................................................................................................ 33 Sampling Section .................................................................................................. 33 Methods and Procedures....................................................................................... 35 5.3 Data Correlation and Evaluation..................................................................... 37 Solubility of Hydrocarbons in Water.................................................................... 37 Solubility of Water in Hydrocarbons.................................................................... 39 5.4 Results and Discussion................................................................................... 40 Benzene Solubility in Water ................................................................................. 42 Water Solubility in Benzene ................................................................................. 43 Toluene Solubility in Water.................................................................................. 44 Water Solubility in Toluene.................................................................................. 45 3-Methylpentane Solubility in Water.................................................................... 46 Water Solubility in 3-Methylpentane.................................................................... 47 5.5 Conclusions..................................................................................................... 48 5.6 Nomenclature.................................................................................................. 49 5.7 Literature Cited............................................................................................... 50 CHAPTER 6. CONCLUSIONS AND RECOMMENDATIONS ................................ 74 6.1 Conclusions..................................................................................................... 74 6.2 Recommendations........................................................................................... 75 CHAPTER 7. OVERVIEW 77 7.1 Rationale ......................................................................................................... 77 7.2 Objectives ....................................................................................................... 79 7.3 Dissertation Organization............................................................................... 79 CHAPTER 8. INFINITE-DILUTION ACTIVITY COEFFICIENT MODELS .......... 81 8.1 Theoretical Models........................................................................................
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