Towards Zero Carbon Emissions: Novel Low Pressure Molecular Natural Gas/CO2/H2 Storage and Separation using Semi-Clathrates
Lead Research Organisation:
Heriot-Watt University
Department Name: Institute Of Petroleum Engineering
Abstract
Recent work carried out in this laboratory has revealed that considerable volumes of low molecular weight gases, including methane, CO2 and hydrogen, can be incorporated into structural cavities of a class of little known clathrate hydrates (or 'gas hydrates'), namely the semi-clathrate hydrates of Quaternary Ammonium Salts (QAS, e.g. tetra-n-butylammonium bromide (TBAB) at very low pressures (to atmospheric) and ambient temperature (30 oC). In addition to favourable conditions of thermodynamic stability, QAS hydrates have numerous further advantageous properties, including:1. The relative ease with which they can be formed/dissociated (by modest pressure and/or gentle temperature change) 2. The potential capacity to store large volumes of gas (62 and 52 vol/vol achieved for CH4 and H2 respectively in our preliminary experiments)3. The capability to strongly discriminate between different gases during gas uptake/hydrate growth (controlled by QAS type and aqueous concentration)4. The ability to produce readily transportable (e.g. in batch reactors, pipelines) hydrate-water slurries5. A very low parent liquid vapour pressure (similar to common salt solutions), meaning gases released from hydrates are of a very high purity (unlike for other volatile organic hydrate promoters such as THF/tetrahydrofuran)6. A relatively low toxicity compared with other organic hydrate promoters (e.g., THF) and chemicals used in gas processing (e.g., amine solutions)These properties give QAS semi-clathrates significant potential as a novel tool for the industrial storage/transportation and separation of gases. Based on the strength of results to date, a patent for this technology has been filed (GB 0511546.4: A method for gas storage, transport, peak-shaving, and energy conversion (2005)). The aim of the work proposed here is to assess the potential of this family of hydrate formers through an intensive integrated experimental and theoretical study. The technology will be investigated using three gases chosen specifically for their current importance in the global energy industry, namely natural gas (NG)/methane (CH4), carbon dioxide (CO2) and hydrogen (H2).
Publications
Chapoy A
(2013)
Clathrate hydrate equilibria in light olefins and mixed methane-olefins systems
in Fluid Phase Equilibria
Chapoy A
(2010)
Experimental Clathrate Dissociations for the Hydrogen + Water and Hydrogen + Tetrabutylammonium Bromide + Water Systems
in Journal of Chemical & Engineering Data
Gholinezhad J
(2011)
Separation and capture of carbon dioxide from CO2/H2 syngas mixture using semi-clathrate hydrates
in Chemical Engineering Research and Design
Jebraeel Gholinezhad (Co-Author)
(2010)
Towards Zero Carbon Emissions: Novel Low Pressure Molecular Natural Gas/CO2/H2 Storage and Separation Using Semi-Clathrate Hydrates
Jebraeel Gholinezhad (Co-Author)
(2011)
Determination of Intrinsic Rate Constant for Hydrate Formation in the Methane-TBAB-Water System
Jebraeel Gholinezhad (Co-Author)
(2011)
Thermodynamic Stability and Self-Preservation Properties of Semi-Clathrates in the Methane+Tetra-n-Butyl Ammonium Bromide+Water System
Jebraeel Gholinezhad (Co-Author)
(2011)
Pre-Combustion Capture of CO2 from Synthesis Gas Mixture CO2/H2 Using Hydrate Formation
Description | We found that quaternary ammonium salts can reduce hydrate formation temperature significantly. This could provide an opportunity for low pressure storage of natural gas and/or nitrogen. However, the low saturation of gas in the semiclathrates may reduce its commercial opportunity. |
Exploitation Route | For low storage of hydrogen and natural gas |
Sectors | Education Energy Environment |
Description | It has been referred in many publications. |