本文選題：正滲透 + 復(fù)合膜��； 參考：《哈爾濱工業(yè)大學(xué)》2015年碩士論文

【摘要】：正滲透(FO)膜分離技術(shù)以其不需外加壓力驅(qū)動、低能耗、低成本、高回收率、抗膜污染等特點逐漸成為膜分離技術(shù)領(lǐng)域研究的熱點,目前在多個領(lǐng)域展示了很好的應(yīng)用前景,得到了一定程度的工程應(yīng)用。但是FO依然有自身的局限性,這些局限主要涉及以下幾個方面:首先,沒有方便并且經(jīng)濟地回收或被濃縮的汲取液;其次,FO膜內(nèi)濃差極化比較嚴(yán)重;此外,溶質(zhì)反向擴散也是FO過程中一個不可忽視的問題;但是限制FO發(fā)展最核心的因素是沒有合適的FO膜。因此,研究制備高性能FO膜顯得十分有必要,本課題著重研究了支撐層以及聚酰胺活性層的制備條件對高性能磺化聚醚砜正滲透復(fù)合膜(SPES-FO膜)性能的影響,同時還研究了錯流操作條件對提升SPES-FO膜性能的效果。本課題采用浸沒凝膠沉淀相轉(zhuǎn)化法制備SPES-FO膜支撐層,研究了磺化聚醚砜支撐層制備配方及其影響因素。從鑄膜液中聚醚砜質(zhì)量濃度、致孔劑質(zhì)量濃度、刮膜厚度以及磺化聚醚砜的磺化度這幾個因素對支撐層結(jié)構(gòu)的影響展開了相關(guān)研究。優(yōu)化制備條件為:支撐層鑄膜液中聚合物質(zhì)量濃度為16%、致孔劑質(zhì)量濃度為10%、磺化聚醚砜的磺化度為6%、刮膜厚度為120μm,此時制備出的SPES-FO膜的純水通量最大,正滲透Na Cl返混通量也較低。利用自制的界面聚合板框在制備的磺化聚醚砜支撐層上進行界面聚合反應(yīng)生成聚酰胺活性層。分別研究了在不同界面聚合條件下,活性層的結(jié)構(gòu)變化對SPES-FO膜的純水通量和Na Cl返混通量大小的影響。結(jié)果表明,界面聚合最佳熱處理時間為30 s,最佳熱處理溫度為80℃,熱處理時間為1 min。若對Na Cl返混通量沒有特殊高要求時,不進行熱處理時SPES-FO膜的純水通量最高,此時Na Cl返混通量也達到較理想的水平值,而將水相溶液p H調(diào)節(jié)到堿性后進行界面聚合,SPES-FO膜性能出現(xiàn)極大的下滑。在不同的錯流水溫、錯流流速、Na Cl汲取液濃度以及不同膜朝向條件下測試了磺化聚醚砜正滲透復(fù)合膜的性能,研究不同錯流條件對膜性能的影響以優(yōu)化正滲透膜分離過程的操作條件。研究表明,提高錯流水溫和錯流流速都有利于減緩SPES-FO膜的濃差極化,增大Na Cl溶液濃度雖然在一定程度上加劇了膜內(nèi)ICP,但是這三者都能提升膜的純水通量,Na Cl返混通量也會隨之升高。在FO模式下,支撐層內(nèi)發(fā)生的稀釋型ICP為影響膜性能的主要因素;在PRO模式下,活性層表面發(fā)生的稀釋型ECP為影響膜性能的主要因素。
[Abstract]:Due to its characteristics of no additional pressure, low energy consumption, low cost, high recovery rate and resistance to membrane fouling, the membrane separation technology has gradually become a hot spot in the field of membrane separation, and has shown a good application prospect in many fields. A certain degree of engineering application has been obtained. However, FO still has its own limitations, which are mainly related to the following aspects: first, there is no convenient and economical recovery or concentration of the solution; secondly, the concentration polarization of FO film is relatively serious; in addition, The reverse diffusion of solute is also an important problem in FO process, but the most important factor limiting the development of FO is the lack of suitable FO membrane. Therefore, it is necessary to study the preparation of high performance FO membranes. In this paper, the effects of the preparation conditions of the support layer and the active layer of polyamide on the performance of the sulfonated polyethersulfone composite membrane (SPES-FO) are studied. At the same time, the effect of cross-flow operation condition on improving the performance of SPES-FO film is also studied. In this paper, SPES-FO membrane supporting layer was prepared by immersion gel precipitation phase inversion method. The preparation formula of sulfonated polyethersulfone support layer and its influencing factors were studied. The influence of the mass concentration of polyethersulfone, the concentration of pore-forming agent, the thickness of scraping membrane and the sulfonation degree of sulfonated polyethersulfone on the structure of the support layer were studied. The optimum preparation conditions are as follows: the polymer concentration in the casting solution of the supporting layer is 16, the mass concentration of the porogenic agent is 10, the sulfonation degree of sulfonated polyethersulfone is 6 and the thickness of the scraping membrane is 120 渭 m. The pure water flux of the prepared SPES-FO membrane is the largest. The remixing flux of normal permeable NaCl is also low. The polyamide active layer was formed by interfacial polymerization on the supported layer of sulfonated polyethersulfone using the self-made interfacial polymerization plate and frame. The effects of the structure of the active layer on the pure water flux and NaCl backmixing flux of SPES-FO membrane were studied under different interfacial polymerization conditions. The results show that the optimum heat treatment time for interfacial polymerization is 30 s, the optimum heat treatment temperature is 80 鈩，

本文編號：1780139