תפריט נגישות
ניגודיות עדינהניגודיות גבוהה
מונוכרום
הדגשת קישורים
חסימת אנימציה
פונט קריא
סגור
איפוס הגדרות נגישות
להורדת מודול נגישות חינם תפריט נגישותניגודיות עדינהניגודיות גבוההמונוכרוםהדגשת קישוריםחסימת אנימציהפונט קריאסגוראיפוס הגדרות נגישותלהורדת מודול נגישות חינםBatarseh, C., Institute of Chemistry, Casali Center of Applied Chemistry, Center for Nanoscience and Nanotechnology, Hebrew University of Jerusalem, Jerusalem, 91904, Israel; Abu-Reziq, R., Institute of Chemistry, Casali Center of Applied Chemistry, Center for Nanoscience and Nanotechnology, Hebrew University of Jerusalem, Jerusalem, 91904, Israel
This study describes the microencapsulation of deep eutectic solvents (DESs) via a non-aqueous sol-gel technique. The microencapsulation was performed using oil in oil emulsions as templates for the interfacial polycondensation of silane monomers such as tetraethoxyorthosilicate and polydimethoxysiloxane. The non-aqueous polycondensation of the silane monomers was achieved using formic acid, which acted as both a catalyst and a reagent. The process also required the presence of cetyl polyethyleneglycol/polypropyleneglycol-10/1 dimethicone as an emulsifier to stabilize the emulsion droplets. The silica-enclosed compounds were separated by centrifugation and dried to provide powders that were much easier to handle compared to the original, highly viscous DES bulks. These microcapsules were then used as hosts for palladium nanoparticles and applied in the hydrogenation of different unsaturated compounds. In addition, microcapsules containing choline chloride:l-tartaric acid (1:0.5) were used as heterogeneous Brønsted acidic catalysts for the preparation of N-substituted pyrroles. In both cases, the capsules were recycled several times without significant decrease in conversion. This work demonstrates: (1) the efficiency of combining O/O emulsions and formic acid-mediated non-aqueous sol-gel as a technique for microencapsulation, and (2) the benefits of using microencapsulated DESs as heterogeneous catalysts. © 2019 The Royal Society of Chemistry.
Batarseh, C., Institute of Chemistry, Casali Center of Applied Chemistry, Center for Nanoscience and Nanotechnology, Hebrew University of Jerusalem, Jerusalem, 91904, Israel; Abu-Reziq, R., Institute of Chemistry, Casali Center of Applied Chemistry, Center for Nanoscience and Nanotechnology, Hebrew University of Jerusalem, Jerusalem, 91904, Israel
This study describes the microencapsulation of deep eutectic solvents (DESs) via a non-aqueous sol-gel technique. The microencapsulation was performed using oil in oil emulsions as templates for the interfacial polycondensation of silane monomers such as tetraethoxyorthosilicate and polydimethoxysiloxane. The non-aqueous polycondensation of the silane monomers was achieved using formic acid, which acted as both a catalyst and a reagent. The process also required the presence of cetyl polyethyleneglycol/polypropyleneglycol-10/1 dimethicone as an emulsifier to stabilize the emulsion droplets. The silica-enclosed compounds were separated by centrifugation and dried to provide powders that were much easier to handle compared to the original, highly viscous DES bulks. These microcapsules were then used as hosts for palladium nanoparticles and applied in the hydrogenation of different unsaturated compounds. In addition, microcapsules containing choline chloride:l-tartaric acid (1:0.5) were used as heterogeneous Brønsted acidic catalysts for the preparation of N-substituted pyrroles. In both cases, the capsules were recycled several times without significant decrease in conversion. This work demonstrates: (1) the efficiency of combining O/O emulsions and formic acid-mediated non-aqueous sol-gel as a technique for microencapsulation, and (2) the benefits of using microencapsulated DESs as heterogeneous catalysts. © 2019 The Royal Society of Chemistry.
