Experimental investigations on the phase equilibrium of semiclathrate hydrates of carbon dioxide in TBAB with small amount of surfactant
21 Feb 2013-international journal of energy and environmental engineering (Springer Berlin Heidelberg)-Vol. 4, Iss: 1, pp 1-8
TL;DR: In this paper, a semiclathrate hydrate system of carbon dioxide in tetra-n-butylammonium bromide (TBAB) with a small amount of surfactant, sodium dodecyl sulfate (SDS), for 5, 10, and 20 wt.% TBAB to determine the phase equilibrium temperature and pressure conditions.
Abstract: Experimental studies are carried out on a semiclathrate hydrate system of carbon dioxide in tetra-n-butylammonium bromide (TBAB) with a small amount of surfactant, sodium dodecyl sulfate (SDS), for 5, 10, and 20 wt.% TBAB to determine the phase equilibrium temperature and pressure conditions. It is observed that the presence of SDS did not influence the equilibrium conditions of the semiclathrate hydrate. Re-nucleation (memory) effect of semiclathrate hydrates of CO2 is studied for few cases of TBAB concentration in an aqueous solution. The equilibrium pressure and temperature conditions obtained for memory effect and regular experimental run without memory effect were observed to be quite close. It is concluded that in the case of no memory effect, with increasing TBAB percentage in the system, the time required for nucleation is reduced. For the same TBAB concentration, the incipient pressure and temperature required for nucleation and re-nucleation of semiclathrate hydrates increase while the time required for re-nucleation decreases.
Citations
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TL;DR: In this article, the authors gather the researches on CO2 hydrate and the hydrates of gas mixtures of CO2+N2/H2/CH4, including studies of fundamental thermo-physical properties, molecular structures and hydrate formation equilibrium conditions.
Abstract: Hydration is an alternative promising method for CO2 capture and separation from either post-combustion flue gas or pre-combustion fuel gas. The present paper gathers the researches on CO2 hydrate and the hydrates of gas mixtures of CO2+N2/H2/CH4, including studies of fundamental thermo-physical properties, molecular structures and hydrate formation equilibrium conditions. Some promoters, i.e. quaternary ammonium salt etc. are usually used in CO2 hydration process to reduce the hydrate equilibrium pressure and to enhance the hydrate kinetic and stability, hence their promotion effect on CO2 hydrate and on the hydrates of gas mixture of CO2+N2/H2/CH4 are reviewed. The paper also summarizes the applications of hydrate technology in CO2 capture and separation, and the corresponding performance is summarized and the bottlenecks are discussed. It necessitates more works to promote this technology towards industrial application.
174 citations
TL;DR: In this article, the effect of tetra-n-butyl ammonium bromide (TBAB) was systematically investigated at a constant temperature of 279.2 K and pressure of 6.0 MPa.
Abstract: Hydrate based gas separation (HBGS) process for the precombustion capture of CO2 from a fuel gas mixture is a novel method being investigated among the carbon capture and sequestration techniques to reduce CO2 emissions. The efficiency of the HGBS process can be improved by using promoters that reduce the formation pressure of mixed gas hydrates. In this study the effect of tetra-n-butyl ammonium bromide (TBAB) was systematically investigated at a constant temperature of 279.2 K and pressure of 6.0 MPa for different TBAB concentrations of 0.3, 1.0, 1.5, 2.0, and 3.0 mol %, respectively. The 0.3 mol % solutions had a relatively longer average induction time of 20.1 min but exhibited the highest total normalized gas uptake of 0.0104 (±0.0004) mol of gas/mol of water and highest separation factor of 41.51 (±6.391). On the other hand, the 1.0 mol % solution had very short average induction time (<0.5 min) and it had the highest hydrate growth rate of 60.8 (±9.89) mol of gas·min–1·m–3, with the separation fact...
95 citations
TL;DR: In this paper, the authors provide a comprehensive understanding of the CO2 hydrate with focus on the formation and dissociation models, including the kinetic and thermodynamic ones, as well as its applications.
Abstract: Carbon dioxide hydrate has been paid growing attention due to its application potentials like being used as a secondary refrigerant and sequestration in the deep ocean. Therefore, there has been a lot of research on various gas hydrates, including methane hydrate, ethane hydrate, methane–CO2 mixture hydrate and so on. However, there is no review especially on the CO2 hydrate and its cooling application. In this paper, the review provides the comprehensive understanding of the CO2 hydrate with focus on the formation and dissociation models, including the kinetic and thermodynamic ones, as well as its applications. It is proposed that more experimental and modeling work should be carried out on CO2 hydrate dissociation, and the kinetic models should be developed by considering the effect of additives. It is also proposed that the cooling application of CO2 hydrate will become popular in the very near future and therefore, the experimental data at low pressure are needed. Finding the effective additives which can reduce the equilibrium conditions and increase the kinetic formation/dissociation rate is recommended.
88 citations
TL;DR: In this article, experiments were conducted at an initial pressure conditions of 75 MPa and 27615 K for pure water, SDS, TBAB, (Tetra-n-butyl ammonium bromide, tetrahydrofuran, THF) and kinetic promoters (sodium dodecyl sulphate SDS) for methane hydrate system suitable for natural gas storage and transportation.
76 citations
TL;DR: A review of hydrate equilibrium condition is presented in this paper, which is intended to overview and classify the critical studies on hydrate equilibria condition and reveal the aspects in which still further investigations are required.
63 citations
References
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Book•
01 Jan 1990TL;DR: In this paper, the authors compared the properties of hydrates and ice with those of natural gas and showed the effect of thermodynamic inhibitors on the formation of hydrate formation and dissolution process.
Abstract: PREFACE Overview and Historical Perspective Hydrates as a Laboratory Curiosity Hydrates in the Natural Gas Industry Hydrates as an Energy Resource Environmental Aspects of Hydrates Safety Aspects of Hydrates Relationship of This Chapter to Those That Follow Molecular Structures and Similarities to Ice Crystal Structures of Ice Ih and Natural Gas Hydrates Comparison of Properties of Hydrates and Ice The What and the How of Hydrate Structures Hydrate Formation and Dissociation Processes Hydrate Nucleation Hydrate Growth Hydrate Dissociation Estimation Techniques for Phase Equilibria of Natural Gas Hydrates Hydrate Phase Diagrams for Water + Hydrocarbon Systems Three-Phase (LW-H-V) Equilibrium Calculations Quadruple Points and Equilibrium of Three Condensed Phases (LW-H-LHC) Effect of Thermodynamic Inhibitors on Hydrate Formation Two-Phase Equilibrium: Hydrates with One Other Phase Hydrate Enthalpy and Hydration Number from Phase Equilibrium Summary and Relationship to Chapters Which Follow A Statistical Thermodynamic Approach to Hydrate Phase Equilibria Statistical Thermodynamics of Hydrate Equilibria Application of the Method to Analyze Systems of Methane + Ethane + Propane Computer Simulation: Another Microscopic-Macroscopic Bridge Summary Experimental Methods and Measurements of Hydrate Properties Experimental Apparatuses and Methods for Macroscopic Measurements Measurements of the Hydrate Phase Data for Natural Gas Hydrate Phase Equilibria and Thermal Properties Summary and Relationship to Chapters that Follow References Hydrates in the Earth The Paradigm Is Changing from Assessment of Amount to Production of Gas Sediments with Hydrates Typically Have Low Contents of Biogenic Methane Sediment Lithology and Fluid Flow Are Major Controls on Hydrate Deposition Remote Methods Enable an Estimation of the Extent of a Hydrated Reservoir Drilling Logs and/or Coring Provide Improved Assessments of Hydrated Gas Amounts Hydrate Reservoir Models Indicate Key Variables for Methane Production Future Hydrated Gas Production Trends Are from the Permafrost to the Ocean Hydrates Play a Part in Climate Change and Geohazards Summary Hydrates in Production, Processing, and Transportation How Do Hydrate Plugs Form in Industrial Equipment? How Are Hydrate Plug Formations Prevented? How Is a Hydrate Plug Dissociated? Safety and Hydrate Plug Removal Applications to Gas Transport and Storage Summary of Hydrates in Flow Assurance and Transportation APPENDICES INDEX
6,037 citations
TL;DR: In this article, the authors used TBAB as an additive to make the hydrate crystallization condition milder, which made it more suitable for CO2 capture from a gas mixture.
382 citations
"Experimental investigations on the ..." refers background or methods or result in this paper
...The equilibrium data obtained in this work is compared with the equilibrium data available in an open literature [7,11-20]....
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...[11] conducted phase stability experiments on carbon dioxide semiclathrate hydrates for varying TBAB weight percentages from 4....
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...Several researchers [11-20] conducted experiments to determine the equilibrium conditions of semiclathrate hydrate systems....
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...Semiclathrate hydrates have a wide range of engineering applications such as carbon dioxide sequestration, transportation and storage of natural gas, and flue gas separation [11-15]....
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Book•
01 Jan 1981
338 citations
"Experimental investigations on the ..." refers background in this paper
...Memory effect has been studied in the crystallization of clathrate hydrates [22]....
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TL;DR: In this article, the congruent melting points of two types of TBAB hydrates were determined from the phase diagram of semiclathrate hydrate nucleation under the condition of atmospheric pressure, latent and specific heats capacity of TBA-n-butyl ammonium bromide (TBAB) hydrate.
333 citations
Additional excerpts
...It is to be noted here that the heating observed under semiclathrate formation can be used to determine heat of formation along with better analytical techniques, such as calorimetry or differential thermal analysis [12,32,33]; however, this measurement does not form the focus of this work....
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TL;DR: In this paper, the authors present new experimental data at high pressure TBAB, w = 0.10, TBAB (w = 0, 0.20, and 0.43) + natural gas semi-clathrate phase boundaries.
Abstract: Tetrabutyl ammonium bromide (TBAB) forms a semi-clathrate hydrate, which can incorporate small gas molecules such as methane and nitrogen. It has recently been used for separation of gases. However, there are very limited experimental data on the phase boundaries of the gas hydrate form in the presence of TBAB. In this work, we present new experimental data at high-pressure TBAB, w = 0.10, TBAB (w = 0.10 and 0.43) + hydrogen, TBAB (w = 0.05, 0.10, 0.20, and 0.30) + methane, TBAB (w = 0.10) + nitrogen, TBAB (w = 0.1 and 0.427) + carbon dioxide, and TBAB (w = 0.05, 0.10, and 0.43) + natural gas semi-clathrate hydrate phase boundaries. In another part of this work, the results of visual observations of the methane + TBAB semi-clathrate hydrate morphology and the methane gas bubbles released from methane + TBAB semi-clathrate hydrates on dissociation are presented. Finally, the effect of TBAB mass fraction on hydrate promotion and the stability of the new semi-clathrate hydrate are presented.
291 citations
Additional excerpts
...[7] conducted experiments to determine the equilibrium temperature and pressure of semiclathrate hydrates of methane, carbon dioxide, and nitrogen with varying percentages of TBAB in the aqueous system....
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...The equilibrium data obtained in this work is compared with the equilibrium data available in an open literature [7,11-20]....
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...The principal difference is that, unlike true clathrates where the guest molecules are not physically bonded within the water structure, in semiclathrate hydrates, the host/guest molecules of TBAB may form the part of the water lattice (host) as well as occupy cages (guest) along with the gas molecules [7-10]....
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