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Janne Bjmmtvedt Buhaug Investigation of the Chemistry of Liquid H2S Scavengers ,- DISC-LAIMER

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Janne Bjmmtvedt Buhaug Investigation of the Chemistry of Liquid H2S Scavengers ,- DISC-LAIMER Janne Bjmmtvedt Buhaug Investigation of the Chemistry of Liquid H2S Scavengers ,- DISC-LAIMER Portions of this document may be illegible in electronic image products. Images are produced from the best available original document. Janne Bjamtvedt Buhaug INVESTIGATION OF THE CHEMISTRY OF LIQUIDH2S SCAVENGERS DEPARTMENT OF CHEMISTRY NORWEGIAN UNIVERSITY OF SCIENCE & TECHNOLOGY "u Preface The work presented in this dissertation has been executed at the Department of Chemistry, the Norwegian University of Science and Technology in Trond- heim, fiom January 1999 to June 2002. Statoil ASA initiated this work, and I would like to thank them for letting me work on their project. Statoil and the Norwegian Research Council are gratellly acknowledged for their generous financial support. I would like to express my most sincere gratitude to my supervisor, Professor Jan M. Bakke, for his great enthusiasm and belief in me and my work. I am deeply grateful to my friends and colleagues at the Department for many hours of small-talk, fruitful discussions and valuable help during my studies. Particularly, I would particularly like to thank siv.ing. Ingrid Sletvold and sivhg. Bjart Frode Lutnzzs for spending hours reading through this thesis. All your comments have been greatly appreciated. Dr.ing. Einar Skarstad Egeland was very helpful in establishing the WPAC names of many of my compounds, and he is gratefully acknowledged. Finally, I would like to express my gratitude to my family for the many encour- aging phone calls during my many years of education. Lastly, I would like to thank my husband, Halvard, for his love and support, and for colourful ideas for my work. 1 .. 11 Table of Contents SUMMARY .......................................................... vi1 SYMBOLS & ABBREVIATIONS ...................... IX 1 INTRODUCTION ................................................... 1 1.1 H2S Scavenging ..................................................... 1 1.2 Liquid Scavengers: "Triazine".............................. 2 2 THEORY .................................................................. 5 2.1 Dihydrogen SuIfide ............................................... 5 2.1.1 Health Considerations .................................... 5 2.1.2 Chemical Properties ....................................... 5 2.2 1.3. 5-Tnazinanes.. ................................................... 7 2.2.1 Preparation ..................................................... 7 2.2.2 Chemical Properties ....................................... 7 2.2.3 Spectroscopic Data ......................................... 8 2.2.4 Triazinane 1 as H2S Scavenger...................... 9 2.3 NMR Spectroscopy .............................................. 11 2.3.1 Dynamic NMR Spectroscopy...................... 11 2.3.2 NOE Spectroscopy....................................... 12 3 THE HYDROLYSIS OF TRIAZINANE 1 .......... 17 3.1 The Structums of the Products ............................ 17 3.1.1 Results and Discussion ................................ 17 3.2 The Rate of Hydrolysis ........................................ 18 3.2.1 Kinetic Equations......................................... 18 3.2.2 Results and Discussion ................................ 19 3.3 Conclusion .......................................................... 23 4 THE EQUIMOLAR REACTION BETWEEN TRIAZINANE 1 AND HS-.................................... 25 4.1 NMR Analyses ..................................................... 27 4.1.1 'H NMR and 1H,IH COSY Spectra ............. 27 4.1.2 1D NOE spectra ........................................... 28 4.1.3 I3C NMR and HJZTCOR Spectra ................. 29 4.1.4 Investigation of Possible Products ............... 30 . 4.1.5 Assignment of NMR Data ........................... 32 4.2 Separation and lsolation of the Products ........... 34 4.2.1 Liquidniquid Extraction ............................. 35 4.2.2 Gas Chromatography ................................... 35 4.2.3 Thin Layer and Column Chromatography ... 36 4.3 Analyses of Thiadiazinane 2 ............................... 37 4.3.1 Mass Analysis .............................................. 37 4.3.2 Low Temperature 'H NMR Spectra ............. 38 ... Ill 4.3.3 IR spectroscopy ........................................... 39 4.4 the pH-Dependence ofthe Reaction .................. 39 4.5 Conclusion.......................................................... 40 5 THE REACTION BETWEEN TRIAZINANE 1 AND EXCESS HS- ................................................. 41 5.I Thiadiazinane 2 and NaHS................................. 41 5.2 Tnazinane 1 and livo Equivalents of HS........... 43 5.3 Separation andIsolation ofthe Product............. 43 5.3.1 LiquidlLiquid Extraction .............................. 43 5.3.2 Gas Chromatography ................................... 44 5.3.3 Short Path Distillation.................................. 44 5.4 Analysis of Dithiazinane 3 .................................. 44 5.4.1 Mass Analysis .............................................. 44 5.4.2 Low-Temperature 'H NMR Spectra ............ 45 5.4.3 IR spectroscopy ........................................... 47 5.5 Triazinane 1 and Laxe Excess of HS................ 47 5.5.1 Triazinane 1 and Three Equivalents of HS- .47 5.5.2 Tnazinane 1and Five Equivalents of HS-.... 47 5.5.3 Dithiazinane 3 and Four Equivalents of HS48 5.6 Triaznane 1 and Gaseous HP ........................... 49 5.7 Spent Scavenger Solution ................................... 50 5.8 Conclusion.......................................................... 50 6 THE RATE OF THE REACTION BETWEEN TRIAZINANE 1 AND HzS ................................... 55 6.1 Kinetic Equations ............................................... 55 6.2 Method for DeteAination of Sulfide.................. 57 6.2.1 The First Attempt ......................................... 57 6.2.2 The Second Attempt..................................... 58 6.2.3 The Caliiration ofthe Electrode .................. 59 6.2.4 ReproducibilityTests of Sulfide Electrode .. 59 6.2.5 Other Methods for Determination of Sulfide61 6.3 Method for Determination of Triazinane............ 61 6.3.1 The Reactivity of TriaZinane 1..................... 62 6.3.2 Applicability of the Method ......................... 64 6.4 Conclusion.......................................................... 64 7 STABILITY AND REACTIVITY OF OTHER 13,5-TIUAZINANES ............................................ 69 7.1 1.3.5-Triethyl-1.3.5-triazinane ........................... 70 7.1.1 Rate ofHydrolysis ....................................... 70 7.1.2 Reaction products with H2S......................... 72 7.1.3 Rate ofReaction with H2S ........................... 75 iv 7.2 1.3.5.Trimethyl.l. 3. 5.triminane ......................... 76 7.2.1 Rate of Hydrolysis ....................................... 76 7.2.2 Reaction Products With H2S ......................... 78 7.2.3 Rate of Reaction with H2S ........................... 80 7.3 2.4. 6.Trimethyl.l.3.5.tris(2.hydmxyethyI) . 1.3. 5.triazinane ................................................... 81 7.4 Comparison of the Results .................................. 85 7.4.1 Stability ........................................................ 85 7.4.2 Reactivity with H2S ..................................... 86 7.5 Conclusion .......................................................... 87 8 STABILITY AND REACTIVITY OF TRIOXANES, TETROXANES AND AN OXOLANE............................................. 91 8.1 1.3. 5.Trioxane ..................................................... 91 8.2 2.4.6.Trimethyl.1.3. 5.trioxane ............................ 93 8.3 1.3.5. 7.Tetroxane ................................................. 94 8.4 1. 3.Dioxolane ...................................................... 97 8.5 Conclusion .......................................................... 98 9 EXPERIMENTAL............................................... 101 9 .I General ............................................................. 101 9.1.1 Chemicals ................................................... 101 9.1.2 Instrumentation .......................................... 101 9.2 The Synthesis of Triazinane 1 ........................... 103 9.3 The Hydmlysis of Triminane 1 ......................... 103 9.3.1 The Structures ofthe Products ................... 103 9.3.2 The Rate of Hydrolysis .............................. 104 9.4 The Equimolar Reaction between Triazinane 1 and HS .............................................................. 105 9.4.1 NMR Analyses ........................................... 105 9.4.2 Separation and Isolation of the Products ... 107 9.4.3 Analyses of Thiadiazinane 2 ...................... 108 9.5 The Reaction between Triazinane 1 and Excess HS .................................................. 109 9.5.1 Thiadiazinane 2 and NaHS ........................ 109 9.5.2 TriaZinane 1 and lkvo Equivalents of HS- . 109 9.5.3 Separation and Isolation of the Product ..... 110 9.5.4 Analyses of Dithiazinane 3 ........................ 110 9.5.5 Triazinane 1and Large Excess of HS ........ 111 9.5.6 Triazinane 1 and Gaseous H2S ................... 112 9.6 The Rate of the Reaction between Tdminane I and HS......................................... 113 9.6.1 Method for Determination of Sulfide ........ 113 9.6.2 Method for Determination of Triazinane ... 114 V 9.7 Stability and Reactivity of Other 1,3,5-Tri~inanes..................................... 115 9.7.1 1,3J-Tnethyl-l,3,5-triazinane ................... 115 9.7.2 1,3,5-Trimethyl-1,3,5-triazi~ne...............
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