Nitrogen and water adsorption in aluminum methylphosphonate alpha : a molecular simulation study
We present here Monte Carlo simulation and experimental results on the adsorption of nitrogen and water in aluminum methylphosphonate polymorph alpha (AlMePO-alpha). We have assumed a detailed atomic model for the material, using experimental information to construct the simulation cell. Nitrogen wa...
| Veröffentlicht in: | Langmuir : the ACS journal of surfaces and colloids. - 1992. - 22(2006), 7 vom: 28. März, Seite 3097-104 |
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| 1. Verfasser: | |
| Weitere Verfasser: | , , , |
| Format: | Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2006
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| Zugriff auf das übergeordnete Werk: | Langmuir : the ACS journal of surfaces and colloids |
| Schlagworte: | Journal Article |
| Zusammenfassung: | We present here Monte Carlo simulation and experimental results on the adsorption of nitrogen and water in aluminum methylphosphonate polymorph alpha (AlMePO-alpha). We have assumed a detailed atomic model for the material, using experimental information to construct the simulation cell. Nitrogen was modeled with two different approaches: as a simple Lennard-Jones (LJ) sphere with no charges, and as a diatomic molecule with charges explicitly included. Water was represented by the TIP4P model. Experimental adsorption isotherms were used to tune the proposed molecular model for the adsorbent. Simulated adsorption capacities were in agreement with the experimental results obtained for the studied systems. The influence of the surface model on the adsorption behavior was taken into account by considering different values of the surface methyl group size parameter. Our results corroborate the strong sensitivity of the simulation results to this parameter, as previously observed by Schumacher and co-workers. It is also observed that charged models are essential to accurately describe the low-pressure region of the adsorption isotherm, where the solid-fluid interaction rules the system behavior. However, a simple uncharged molecular model for nitrogen is able to describe the three loci arrangement at maximum loading. Experimental and simulation results presented here also confirm the low water affinity of AlMePO-alpha. These results enforce the application of this methodology to achieve quantitative predictions on similar systems, with the appropriate transferability of the molecular parameters |
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| Beschreibung: | Date Completed 06.06.2007 Date Revised 21.03.2006 published: Print Citation Status PubMed-not-MEDLINE |
| ISSN: | 1520-5827 |