本文選題：促進(jìn)傳遞膜 + 二氧化碳分離��； 參考：《浙江工業(yè)大學(xué)》2017年碩士論文

【摘要】：CO2是造成全球變暖的一種主要溫室氣體,且會降低沼氣、天然氣等燃?xì)獾娜紵?腐蝕運輸管道等。因此,分離和回收CO2氣體對環(huán)境和能源都具有非常重要的意義。目前商業(yè)化的CO2氣體分離方法中,膜分離法因其設(shè)備簡單、高效靈活、易于操作、投資低等優(yōu)點而得到越來越多的關(guān)注。制備氣體分離膜的方法有很多,但是用一種綠色、簡單、高效的方法制備CO2氣體分離膜,仍具有很大的挑戰(zhàn)。本文采用靜電自組裝的方法制備兼具高滲透性和高選擇性的CO2促進(jìn)傳遞膜,選用低濃度的聚乙烯亞胺(PEI)水溶液作為自組裝溶液,商業(yè)化的聚酰胺(PA)反滲透膜為底膜。文中對影響自組裝膜性能的因素,包括膜的干濕態(tài)、自組裝方式、PA底膜、自組裝層數(shù)、自組裝時間、進(jìn)料壓力、各種自組裝條件等進(jìn)行了研究,并對膜進(jìn)行了場發(fā)射掃描電子顯微鏡(SEM)、傅里葉變換紅外光譜(FT-IR)、X射線光電子能譜(XPS)、接觸角等的表征。為了使這種制備方法更具有實用性,由對膜片的自組裝,擴(kuò)大到對膜組件的自組裝。(1)在PEI水溶液濃度50 mg/L,pH值8.0,動態(tài)自組裝,自組裝泵壓0.6MPa,操作溫度25℃,自組裝時間1 h條件下,制得的膜具有較高的氣體滲透速率和選擇性。PEI分子在底膜上的吸附,只需有幾十秒就能達(dá)到吸附平衡,且單層自組裝比多層自組裝更具有優(yōu)勢。(2)CO2透過自組裝膜的傳遞是聚合物鏈間增加的自由體積和PEI分子(和H2O分子)的促進(jìn)傳遞兩方面因素共同作用的結(jié)果,而N2的傳遞僅僅只是溶解-擴(kuò)散的結(jié)果。(3)SEM、XPS以及接觸角分析結(jié)果均可以證明膜表面沉積有PEI分子,但是由于自組裝的PEI溶液濃度極低,且為單層自組裝,膜表面PEI分子數(shù)量很少,因此SEM斷面圖和FT-IR表征均得不到關(guān)于組裝的有用信息。(4)將靜電自組裝的制膜方法,從面積為25 cm2的膜片放大到0.5 m2和1.3m2的卷式膜組件,得到的膜組件仍具有較高的氣體分離性能,并且將組件烘干后浸潤,組件氣體分離性能基本保持不變,說明這種制備方法易于放大,所得膜性能穩(wěn)定,不易被破壞,具有很好的實用價值。
[Abstract]:CO2 is one of the main greenhouse gases that cause global warming, and it will reduce the burning value of biogas, natural gas and so on, and corrode the transportation pipeline and so on. Therefore, the separation and recovery of CO2 gas is of great importance to the environment and energy. Among the commercial CO2 separation methods, membrane separation has attracted more and more attention because of its advantages of simple equipment, high efficiency and flexibility, easy operation and low investment. There are many methods to prepare gas separation membrane, but it is still a challenge to prepare CO2 gas separation membrane by a green, simple and efficient method. In this paper, a high permeability and high selectivity CO2 promoted transfer membrane was prepared by electrostatic self-assembly. A low concentration polyethylene imide (PEI) aqueous solution was used as the self-assembly solution, and a commercial polyamide (PAA) reverse osmosis membrane was used as the base membrane. In this paper, the factors affecting the properties of the self-assembled films, including the dry and wet state of the films, the self-assembly mode of PA substrate, the number of self-assembled layers, the self-assembly time, the feed pressure, the various self-assembly conditions, etc. The films were characterized by field emission scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and contact angle. In order to make the preparation more practical, the self-assembly of the membrane was expanded from the self-assembly of the membrane to the self-assembly of the membrane assembly. The pH value of PEI solution was 50 mg / L ~ (-1), the dynamic self-assembly, the pump pressure of self-assembly was 0.6 MPA, and the operating temperature was 25 鈩，

本文編號：2018419