聚氧代氮代苯并環己烷高分子薄膜應用於滲透蒸發分離程序之研究

Polybenzoxazine-based membranes for liquid-liquid pervaporation separation

廖翊伶(Liao, Yi Ling)

指導教授 ： 劉英麟

國立清華大學/工學院/化學工程學系/碩士(2016年)

摘要

本研究針對聚氧代氮代苯并環己烷(PBz)高分子薄膜進行改質，以應用於滲透蒸發分離程序，利用不同進料組成與進料溫度，探討其分離效能與薄膜穩定性。並利用不同方法使PBz高分子膜親水化，進而使其於滲透蒸發分離程序中能有較高的通透量。本研究嘗試摻混具有親水性的高分子如幾丁聚醣以及聚乙烯亞胺、親水性化合物如四乙烯五胺(TEPA)或是摻混鹵化物如1,4-對二氯苯與1,3-二溴丙烷於PBz高分子中，藉由導入親水性材料或是將PBz高分子四級銨化使薄膜親水化，但這些方法無法使PBz薄膜在滲透蒸發分離程序中有較高的通透量。而實驗結果發現將PBz薄膜浸泡於鹼性水溶液的表面處理方式，能使PBz薄膜親水化，並於滲透蒸發分離程序有較高的通透量，但此方法不適用於異丙醇水溶液系統；於四氫呋喃水溶液系統下，PBz-10薄膜的通透量可提升1.2至1.7倍且未降低其分離效能。PBz薄膜以及PBz-10薄膜在不同的進料溫度(25至55℃)與在廣泛的進料濃度(30至90 wt% THF)下，其滲透蒸發測試結果及穩定性表現良好。

關鍵字

滲透蒸發 ； 氧代氮代苯并環己烷

並列摘要

Polybenzoxazine (PBz) membranes with modification have been used for liquid-liquid pervaporation separation by different feed concentrations and different feed temperatures to investigate the separation performance and the membrane stability in this research. We used many methods to make PBz membrane more hydrophilic in order to increase the pervaporation separation flux. We tried PBz to blend with not only hydrophilic materials such as chitosan, poly(ethyleneimine) and tetraethylenepentamine (TEPA) but also halides like p-xylylene dichloride and 1,3-dibromopropane which made PBz quaternized to increase the membrane hydrophilicity. But these methods didn’t work in the increase of the pervaporation separation flux. It shows that immersing the PBz membrane in a basic NaOH aqueous solution made it more hydrophilic and showed higher pervaporation separation flux. However, the surface modification was not appropriate for isopropanol aqueous solutions system. The PBz-10 membrane shows high pervaporation separation flux which are about 1.2-fold to 1.7-fold of the value measured with the PBz membrane without decreasing the separation performance at the system of tetrahydrofuran aqueous solutions. In this work, the PBz membrane and the PBz-10 membrane are effective for pervaporation dehydration on tetrahydrofuran aqueous solutions in a wide concentration range of 30 to 90 wt% and a wide temperature range of 25 to 55℃.

並列關鍵字

pervaporation ； benzoxazine

參考文獻

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