Gas Hydrates 1

Daniel Broseta is Professor and member of the Laboratory of Complex Fluids and their Reservoirs at the University of Pau and Pays de l'Adour in France. His research interests are in interfacial and colloidal phenomena.Livio Ruffine is a research scientist at the French Research Institute for the Exploitation of the Sea (Ifremer) in Brest, France. His research interests focus on the oceanic methane cycle, with an emphasis on the geochemical dynamics of gas-hydrate deposits.Arnaud Desmedt is a CNRS researcher at the Institute of Molecular Science at the University of Bordeaux in France. His main research interests are molecular spectroscopy (experimental and modelling) applied to inclusion chemistry and fundamental issues on clathrate hydrates.

• Preface ixChapter 1 Neutron Scattering of Clathrate and Semiclathrate Hydrates 1Arnaud DESMEDT, Laura BEDOURET, Jacques OLLIVIER and Claire PETUYA1.1 Introduction 11.2 Neutron scattering 21.2.1 A basic ideal scattering experiment 31.2.2 Neutron scattering theory 41.2.3 Correlation functions 61.2.4 Coherent and incoherent scattering 71.2.5 A simple example of scattering 111.3 Probing structural and dynamical properties of gas hydrates 141.3.1 Structures 151.3.2 Relaxation of guest molecules and water molecules 161.3.3 Excitations and vibrational density of states 191.4 Selected examples 221.4.1 Inhibition and formation mechanisms 221.4.2 Guest replacement in gas hydrates 291.4.3 Hydrogen: from its dynamics properties to its storage capabilities 331.4.4 Ionic clathrate hydrates and semiclathrates 411.5 Concluding remarks 471.6 Bibliography 49Chapter 2 Spectroscopy of Gas Hydrates: From Fundamental Aspects to Chemical Engineering, Geophysical and Astrophysical Applications 63Bertrand CHAZALLON, Jennifer A. NOBLE and Arnaud DESMEDT2.1 Introduction 632.2 Vibrational spectrum 652.2.1 Intramolecular modes 662.2.2 Intermolecular modes 682.3 Applications to the investigation of formation mechanism 722.3.1 Formation mechanism: nucleation and growth 722.3.2 The Raman contribution 742.3.3 Insights from IR spectroscopy 772.3.4 Formation mechanism: chemical engineering applications 812.4 NGHs: contribution of spectroscopy 842.5 Clathrate hydrates in astrophysical environments 922.5.1 IR spectroscopy of astrophysical ices 932.5.2 Interstellar ices 942.5.3 Solar system ices 962.5.4 Insights from laboratory spectroscopy 1002.6 Concluding remarks 1012.7 Bibliography 102Chapter 3 High-Resolution Optical Microscopy of Gas Hydrates 113Nelly HOBEIKA, Maria Lourdes MARTINEZ DE BAÑOS, Patrick BOURIAT, Daniel BROSETA and Ross BROWN3.1 Introduction 1133.2 Optical methods 1143.2.1 Beyond bright-field modes in optical microscopy 1143.2.2 Brewster angle microscopy 1233.3 Selected examples 1263.3.1 Hydrate halos growing on glass substrates 1283.3.2 Hydrate crystallization in a guest-in-water emulsion 1313.3.3 Adsorption of kinetic hydrate inhibitors 1363.4 Concluding remarks 1413.5 Acknowledgments 1423.6 Bibliography 142Chapter 4 Calorimetric Characterization of Clathrate and Semiclathrate Hydrates 145Didier DALMAZZONE, Luiz Paulo SALES SILVA, Anthony DELAHAYE and Laurence FOURNAISON4.1 Introduction 1454.2 DTA and differential scanning calorimetry 1464.2.1 Principles of DTA and DSC 1464.2.2 Examples of pressure-controlled DTA and DSC devices for hydrate studies 1474.2.3 Temperature calibration of DSC 1524.3 Phase equilibrium determination in hydrate systems using pressure-controlled TDA and DSC 1534.3.1 Proper exploitation of DSC thermograms 1534.4 Measuring the heat of dissociation and heat capacity of gas hydrates 1584.4.1 Quantitative in situ hydrate formation 1604.4.2 Indirect enthalpy measurement and gas content evaluation 1624.4.3 Heat capacity measurement 1634.5 Measuring the kinetics of hydrate formation 1664.6 Conclusion 1684.7 Bibliography 169Chapter 5 Thermodynamic Modeling of Solid–Fluid Equilibria: From Pure Solid Phases to Gas Semiclathrate Hydrates 177Patrice PARICAUD5.1 Introduction 1775.2 Solid–fluid equilibrium between a fluid mixture and a pure solid phase 1795.2.1 Solid–liquid equilibrium condition 1795.2.2 SLE in the presence of electrolyte solutions 1855.2.3 Solid–fluid equilibrium condition 1885.3 Solid–liquid equilibrium between a liquid mixture and a solid solution 1895.4 SLE between a liquid mixture and a solid compound 1925.4.1 Solid–liquid equilibrium with salt hydrates 1925.4.2 Solid–liquid equilibrium with semiclathrate hydrates 1995.5 Thermodynamic model for gas semiclathrate hydrates 2025.5.1 Paricaud’s approach 2035.5.2 The Eslamimanesh et al model 2135.6 Conclusion 2155.7 Bibliography 215Chapter 6 Volume and Non-Equilibrium Crystallization of Clathrate Hydrates 227Baptiste BOUILLOT and Jean-Michel HERRI6.1 Introduction 2276.2 Driving force and evidence for non-equilibrium gas hydrate crystallization 2296.2.1 Driving force 2296.2.2 Cage occupancy from equilibrium thermodynamics 2336.3 Non-equilibrium hydrate formation? 2356.3.1 Evidence from experimental studies 2366.3.2 Clathrate hydrates in fluid inclusions 2386.3.3 Evidence from molecular dynamics 2396.3.4 Experimental and modeling issues 2406.4 Modeling gas to hydrate transfer: equilibrium thermodynamics versus kinetics 2416.5 Non-equilibrium flash calculations 2426.5.1 Basics of flash calculations 2426.5.2 Conventional flash approach for clathrate hydrates 2436.5.3 Conclusions on standard flash approaches 2486.5.4 Non-stoichiometric flash approaches 2496.5.5 Discussion 2556.6 A kinetic Langmuir based modeling approach 2586.6.1 Introduction to the kinetic approach of mixed hydrates 2586.6.2 Kinetic approach of enclathration 2676.7 Conclusion 2746.8 Nomenclature 2746.8.1 Letters 2746.8.2 Greek letters 2756.8.3 Subscript 2766.8.4 Superscript 2766.9 Bibliography 276List of Authors 283Index 285