Effect of silk fibroin membrane microstructure on pervaporation performance
| Autor: | Jui-Han Liang, 梁睿涵 |
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| Rok vydání: | 2016 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 104 Silk fibroin is used as the main component of the present membrane due to its advantageous mechanical properties and uniform weight distribution. Silk fibroin membranes are prepared through a subsequent alcohol treatment which addresses the silk fibroin’s instability in water by the formation of stable β-sheet structures. Variation in drying temperature, alcohol used, alcohol concentration, and immersion time was performed to find the optimal conditions for silk fibroin membranes’ pervaporation applications against 70 wt% IPA. Microstructural and morphology changes were discerned via ATR-FTIR, XRD and SEM characterization and, surface hydrophilicity were determined via water contact angle and AFM. Based on the pervaporation performance test, longer immersion times resulted to lower permeation fluxes and higher selectivities. This is possibly due to the increase in the formation β-sheet structures which provide additional mass transfer resistance. Next, using low molecular weight alcohols were also found to lower permeation fluxes due to its ability to penetrate easily into the polymer chain and enhance the formation of more β-sheets structures. In conclusion, it was found that immersion in 90 wt% methanol produce the best pervaporation performance with a selectivity of 98.8% and a permeation flux of 1023 g/m2h at 25oC. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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