Chemical Engineering – Gas Processing and Transmission
Cyrus Fallahi; Sadegh Moradi; Reza Masayebi Behbahani
Abstract
In the present study, the permeabilities of CO2 and CH4 in terms of ideal and actual CO2/CH4 selectivity were investigated through the synthesized membranes of poly (ether-block-amide) (Pebax 1657) accompanied with poly (ethylene glycol) (PEG 400) and NH2-MIL125 nanoparticles. NH2-MIL125 nanofillers ...
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In the present study, the permeabilities of CO2 and CH4 in terms of ideal and actual CO2/CH4 selectivity were investigated through the synthesized membranes of poly (ether-block-amide) (Pebax 1657) accompanied with poly (ethylene glycol) (PEG 400) and NH2-MIL125 nanoparticles. NH2-MIL125 nanofillers were added to the blend of PEG 400 and Pebax 1657 at various weight fractions to fabricate polymeric nanocomposite membranes. Several analyses such as the crystalline structure of the synthesized membranes, field emission scanning electron microscopy (FESEM) and X-ray diffraction analysis (XRD) were utilized to investigate the cross-sectional and surface morphology of the membranes; the formation of the chemical bonds was identified by Fourier transform infrared (FTIR). This study presents the permeation of both pure and mixed gases ofmethane and carbon dioxide through Pebax 1657, Pebax/PEG blend, and the Pebax/PEG/NH2-MIL125 nanocomposite membranes in a pressure range of 2-8 bar and at ambient temperature. The findings demonstrated that the synthesized nanocomposite membranes had a positive effect on the separation performance in comparison with the membranes made of neat polymer and polymer blends.
Tahereh Asadi; Mohammadreza Ehsani
Abstract
Copper trimesate (Cu-BTC) MOF has been pointed out as a promising adsorbent for separating carbon dioxide from methane. However, MOF’s need to be shaped prior to their use in packed bed adsorbers in order to reduce pressure drop; on the other hand, the production of mechanically resistant shaped ...
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Copper trimesate (Cu-BTC) MOF has been pointed out as a promising adsorbent for separating carbon dioxide from methane. However, MOF’s need to be shaped prior to their use in packed bed adsorbers in order to reduce pressure drop; on the other hand, the production of mechanically resistant shaped bodies reduces their adsorption performance. In this work, Cu-BTC tablets provided by BASF are evaluated to perform CO2/CH4 separation through adsorption. The adsorption capacity of pure carbon dioxide from methane was measured in a magnetic suspension balance between temperatures of 308 and 373 K up to a pressure of 700 kPa. The evaluated material presents higher adsorption capacity than previously studied shaped samples with a carbon dioxide and methane adsorption capacity up to 3.07 and 0.63 mol/kg at 100 kPa and 308 K respectively. Moreover, the experimental data were fitted with the Langmuir model. Isosteric heats of adsorption were obtained to be 22.8 and 15.1 kJ/mol for CO2 and CH4 on Cu-BTC tablets respectively, which indicates a strong adsorption of carbon dioxide on these adsorbents. Also, single and binary breakthrough curves were measured in the same temperature range and atmospheric pressure by using Cu-BTC tablets as the adsorbent. The preferential adsorption capacity of CO2 on nanoporous copper trimesate (Cu-BTC) indicates that this material can be used for methane purification from natural gas.