Recycling nanoparticles stabilized in water-in-CO2 microemulsions for catalytic hydrogenations
Catalytic hydrogenations of olefins took place effectively in supercritical CO2 with Pd0 nanoparticles dispersed in the fluid phase using a water-in-CO2 microemulsion consisting of water, sodium bis(2-ethylhexyl) sulfosuccinate (AOT) as a surfactant, and 1-octanol as a cosolvent. The hydrogenated pr...
Veröffentlicht in: | Langmuir : the ACS journal of surfaces and colloids. - 1992. - 21(2005), 5 vom: 01. März, Seite 1738-44 |
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Weitere Verfasser: | , |
Format: | Aufsatz |
Sprache: | English |
Veröffentlicht: |
2005
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Zugriff auf das übergeordnete Werk: | Langmuir : the ACS journal of surfaces and colloids |
Schlagworte: | Journal Article |
Zusammenfassung: | Catalytic hydrogenations of olefins took place effectively in supercritical CO2 with Pd0 nanoparticles dispersed in the fluid phase using a water-in-CO2 microemulsion consisting of water, sodium bis(2-ethylhexyl) sulfosuccinate (AOT) as a surfactant, and 1-octanol as a cosolvent. The hydrogenated products dissolved in supercritical CO2 can be separated from the octanol solution containing AOT microemulsions with Pd0 nanoparticles by phase separation (upper phase, supercritical CO2 with hydrogenated products; lower phase, 1-octanol containing AOT microemulsions with Pd0 nanoparticles) accompanied by reduction of CO2 pressure. After collecting the hydrogenated products by flowing the upper CO2 phase to a collection vessel, the Pd0 nanoparticles remaining in the lower phase can be redispersed into supercritical CO2 by pressurizing the system to a pressure where a homogeneous phase is attained. The redispersed nanoparticles can be reused as catalysts for the next runs of the hydrogenations. Triphenylethylene was hydrogenated to 1,1,2-triphenylethane at conversions of 100% (1st-3rd runs), >99% (4th run), and >96% (5th run) using the recycled Pd0 nanoparticles. The feasibility of using other organic solvents as cosolvents is also studied in the present paper |
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Beschreibung: | Date Completed 13.06.2006 Date Revised 22.02.2005 published: Print Citation Status PubMed-not-MEDLINE |
ISSN: | 1520-5827 |