(16c) Adsorptive Removal of CO2 from Natural Gas
AIChE Spring Meeting and Global Congress on Process Safety
2018
2018 Spring Meeting and 14th Global Congress on Process Safety
18th Topical Conference on Gas Utilization
Advances in Gas Processing Design, Purification, and Separation I
Monday, April 23, 2018 - 2:30pm to 3:00pm
Raw natural gas contains methane as its major component, but it also contains considerable amounts of contaminants such as CO2 and H2S (i.e. acid gases) that can cause corrosion and fouling of the pipeline and equipment during transportation and liquefaction. Amine-based CO2 gas removal processes have been employed in the gas industry, but these processes have disadvantages including high regeneration energy requirements and inefficiencies; these issues have not been adequately solved to date. Currently, adsorptive acid gas removal technologies have received significant interest because of the simplicity of adsorbent regeneration by thermal or pressure variation[1]. Numerous micro- and mesoporous adsorbents including zeolites [2-3], titanosilicates[4], activated carbons[5-6], metal-organic-framework (MOF) [7], and silica-alumina materials[8-9] were studied for this type of application. However, the CO2/CH4 selectivity of the aforementioned adsorbents was not high enough for commercial applications. In this study, different adsorbents including cation-exchanged zeolites and amine-modified MOFs were synthesized, physicochemically characterized, and evaluated for adsorptive removal of CO2 from natural gas. The equilibrium isotherms of CO2 and CH4 on adsorbents in varied pressure were measured and compared. The ideal-adsorbed solution theory (IAST) was employed for the estimation of CO2/CH4 selectivity of those adsorbents.
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