Cryogenic Noble Gas Separation without Distillation: The Effect of Carbon Surface Curvature on Adsorptive Separation
Applying a novel self-consistent Feynman−Kleinert−Sesé variational approach (Sesé, L. M. Mol. Phys.1999, 97, 881−896) to quantum thermodynamics and the ideal adsorbed solution theory, we studied adsorption and equilibrium separation of 20Ne−4He mixtures in carbonaceous nanomaterials consisting of...
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| Format: | Journal Article |
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American Chemical Society
2012
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| Online Access: | http://hdl.handle.net/20.500.11937/27131 |
| _version_ | 1848752178639929344 |
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| author | Kowalczyk, Piotr Gauden, P. Terzyk, A. |
| author_facet | Kowalczyk, Piotr Gauden, P. Terzyk, A. |
| author_sort | Kowalczyk, Piotr |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Applying a novel self-consistent Feynman−Kleinert−Sesé variational approach (Sesé, L. M. Mol. Phys.1999, 97, 881−896) to quantum thermodynamics and the ideal adsorbed solution theory, we studied adsorption and equilibrium separation of 20Ne−4He mixtures in carbonaceous nanomaterials consisting of flat (graphite-like lamellar nanostructures) and curved (triply periodic minimal carbon surfaces) nanopores at 77 K. At the infinite mixture dilution, Schwarz P-carbon and Schoen G-carbon sample represents potentially efficient adsorbents for equilibrium separation of 20Ne−4He mixtures. The equilibrium selectivity of 20Ne over 4He (αNe−He) computed for Schwarz P-carbon and Schoen G-carbon sample is very high and reaches 219 and 163 at low pore loadings, respectively. Graphite-like lamellar nanostructures with interlamellar spacing (Δ) less than 0.6 nm are also potential adsorbents for equilibrium separation of 20Ne−4He mixtures at cryogenic temperatures. Here, αNe−He of 80 is predicted for Δ = 0.46 nm at low pore loadings. The quantum-corrected molar enthalpy of 20Ne adsorption strongly depends on the curvature of carbon nanopores.For Schwarz P-carbon sample, it reaches 8.2 kJ mol−1, whereas for graphite-like lamellar nanostructures the maximum enthalpy of 20Ne physisorption of 5.6 kJ mol−1 is predicted at low pore loadings. In great contrast, the quantum-corrected molar enthalpy of 4He adsorption is only slightly affected by the curvature of carbon nanopores. The maximum heat released during the 4He physisorption is 3.1 (Schwarz P-carbon) and 2.7 kJ mol−1 (graphite-like lamellar nanostructure consisting of the smallest flat carbon nanopores). Interestingly, for all studied carbonaceous nanomaterials consisting of curved/flat nanopores, αNe−He computed for the equimolar composition of 20Ne−4He gaseous phases is still very high at total mixture pressure up to 1 kPa. This circumstance is indicative of the possibility of carrying out the adsorption separation of 20Ne−4He mixtures at pt < 1 kPa and 77 K that do not require high-energy consumption. Presented potential models and simulation methods will further enhance the accuracy of modeling of confined inhomogeneous quantum fluids at finite temperatures. |
| first_indexed | 2025-11-14T08:04:30Z |
| format | Journal Article |
| id | curtin-20.500.11937-27131 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T08:04:30Z |
| publishDate | 2012 |
| publisher | American Chemical Society |
| recordtype | eprints |
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| spelling | curtin-20.500.11937-271312017-09-13T16:09:11Z Cryogenic Noble Gas Separation without Distillation: The Effect of Carbon Surface Curvature on Adsorptive Separation Kowalczyk, Piotr Gauden, P. Terzyk, A. Applying a novel self-consistent Feynman−Kleinert−Sesé variational approach (Sesé, L. M. Mol. Phys.1999, 97, 881−896) to quantum thermodynamics and the ideal adsorbed solution theory, we studied adsorption and equilibrium separation of 20Ne−4He mixtures in carbonaceous nanomaterials consisting of flat (graphite-like lamellar nanostructures) and curved (triply periodic minimal carbon surfaces) nanopores at 77 K. At the infinite mixture dilution, Schwarz P-carbon and Schoen G-carbon sample represents potentially efficient adsorbents for equilibrium separation of 20Ne−4He mixtures. The equilibrium selectivity of 20Ne over 4He (αNe−He) computed for Schwarz P-carbon and Schoen G-carbon sample is very high and reaches 219 and 163 at low pore loadings, respectively. Graphite-like lamellar nanostructures with interlamellar spacing (Δ) less than 0.6 nm are also potential adsorbents for equilibrium separation of 20Ne−4He mixtures at cryogenic temperatures. Here, αNe−He of 80 is predicted for Δ = 0.46 nm at low pore loadings. The quantum-corrected molar enthalpy of 20Ne adsorption strongly depends on the curvature of carbon nanopores.For Schwarz P-carbon sample, it reaches 8.2 kJ mol−1, whereas for graphite-like lamellar nanostructures the maximum enthalpy of 20Ne physisorption of 5.6 kJ mol−1 is predicted at low pore loadings. In great contrast, the quantum-corrected molar enthalpy of 4He adsorption is only slightly affected by the curvature of carbon nanopores. The maximum heat released during the 4He physisorption is 3.1 (Schwarz P-carbon) and 2.7 kJ mol−1 (graphite-like lamellar nanostructure consisting of the smallest flat carbon nanopores). Interestingly, for all studied carbonaceous nanomaterials consisting of curved/flat nanopores, αNe−He computed for the equimolar composition of 20Ne−4He gaseous phases is still very high at total mixture pressure up to 1 kPa. This circumstance is indicative of the possibility of carrying out the adsorption separation of 20Ne−4He mixtures at pt < 1 kPa and 77 K that do not require high-energy consumption. Presented potential models and simulation methods will further enhance the accuracy of modeling of confined inhomogeneous quantum fluids at finite temperatures. 2012 Journal Article http://hdl.handle.net/20.500.11937/27131 10.1021/jp305613f American Chemical Society restricted |
| spellingShingle | Kowalczyk, Piotr Gauden, P. Terzyk, A. Cryogenic Noble Gas Separation without Distillation: The Effect of Carbon Surface Curvature on Adsorptive Separation |
| title | Cryogenic Noble Gas Separation without Distillation: The Effect of Carbon Surface Curvature on Adsorptive Separation |
| title_full | Cryogenic Noble Gas Separation without Distillation: The Effect of Carbon Surface Curvature on Adsorptive Separation |
| title_fullStr | Cryogenic Noble Gas Separation without Distillation: The Effect of Carbon Surface Curvature on Adsorptive Separation |
| title_full_unstemmed | Cryogenic Noble Gas Separation without Distillation: The Effect of Carbon Surface Curvature on Adsorptive Separation |
| title_short | Cryogenic Noble Gas Separation without Distillation: The Effect of Carbon Surface Curvature on Adsorptive Separation |
| title_sort | cryogenic noble gas separation without distillation: the effect of carbon surface curvature on adsorptive separation |
| url | http://hdl.handle.net/20.500.11937/27131 |