本文選題：正滲透 + 納濾��； 參考：《中國(guó)海洋大學(xué)》2015年碩士論文

【摘要】：本文用界面聚合法制備出新型高性能含碳納米管的復(fù)合正滲透膜。并探索了制備多孔支撐層和表面分離層的工藝條件,得出了最佳制膜條件。將碳納米管添加到多孔支撐層和表面分離層中,探究了復(fù)合膜中碳納米管的含量和管徑對(duì)膜的滲透性能和結(jié)構(gòu)的影響。此外,還對(duì)膜的正滲透,納濾性能和抗污能力進(jìn)行了測(cè)試,并得出以下主要結(jié)論：膜的水通量隨著基膜鑄膜液中致孔劑的含量的增加而提高,異丙醇溶脹也可提高膜通量,但提高不太明顯,通量不超過(guò)1.0 L/(m2h)。表面分離層的制備條件的探究最終確定膜的制備條件為：致孔劑含量8 g,界面聚合反應(yīng)時(shí)間為30 s,界面聚合水相反應(yīng)單體濃度為0.5%,油相單體濃度為0.1%。多巴胺改性濃度為2g/L,改性時(shí)間24 h。改性膜獲得了4.05 L/(m2h)的通量,而反混通量相對(duì)于改性基底明顯下降,Js/J,約為0.13g/L。復(fù)合膜的水通量隨著改性層中碳納米管含量的增加先增大后減小。當(dāng)改性層中碳納米管添加量為0.05%時(shí),膜獲得最大正滲透通量,水通量由原膜的2.30L/(m2h)上升到4.92 L/(m2h),對(duì)NaCl的截留率保持在90%。對(duì)于氯化鎂/純水體系,復(fù)合膜獲得最大水通量為7.24 L/(m2h), Js/Jv約為0.42g/L。多壁碳納米管比單壁管使復(fù)合膜更高地提高膜的水通量,并獲得更低的反混通量。此外,當(dāng)支撐層中碳納米管添加含量為0.15%時(shí),膜獲得氯化鎂/純水體系最大通量為7.15L/(m2h)：當(dāng)支撐層和改性層中都添加碳納米管時(shí),復(fù)合膜獲得最大水通量為8.25L/(m2h),Js/Jv約為0.03g/L。與純聚酰胺膜相比,在支撐層和改性層中都添加碳納米管的復(fù)合正滲透膜能獲得更高的水通量,同時(shí)保持其截留率。在4 bar操作壓力下,基膜添加0.15%、改性層添加0.05%的復(fù)合膜水通量為29.33 L/(m2h),對(duì)200 ppm MgCl2的截留率為40%,而純聚酰胺膜的水通量為20.89 L/(m2h),截留率為41%。所制備的正滲透復(fù)合膜抗污能力明顯高于純聚酰胺膜,3次污染-清洗-恢復(fù)循環(huán)后,改性層中添加量為0.05%的復(fù)合膜正滲透的水通量恢復(fù)率為80.1%,納濾通量恢復(fù)率為51.5%,而純聚酰胺膜的分別為73.4%和35.9%。
[Abstract]:In this paper, a novel high performance carbon nanotube composite percolation membrane was prepared by interfacial polymerization. The preparation conditions of porous supporting layer and surface separation layer were investigated and the optimum conditions of membrane preparation were obtained. Carbon nanotubes (CNTs) were added to porous support layer and surface separation layer to investigate the effect of the content and diameter of CNTs on the permeability and structure of the membrane. In addition, the direct permeation, nanofiltration and antifouling properties of the membrane were tested. The main conclusions were as follows: the water flux of the membrane increased with the increase of the content of pore-forming agent in the casting solution of the base membrane, and the flux of the membrane was also increased by the swelling of isopropanol. But the increase was not obvious and the flux was not more than 1.0 L / (m2h). The preparation conditions of the surface separation layer are as follows: the content of pore-forming agent is 8 g, the reaction time is 30 s, the monomer concentration of aqueous phase is 0.5 and the concentration of oil monomer is 0.1. The modified concentration of dopamine was 2 g / L and the modification time was 24 h. The flux of modified membrane was 4.05 L / (m2h), while the flux of reverse mixing decreased significantly compared with the modified substrate, about 0.13 g / L. The water flux of the composite membrane increased firstly and then decreased with the increase of carbon nanotube content in the modified layer. When the amount of carbon nanotubes added in the modified layer was 0.05, the maximum positive osmotic flux was obtained, the water flux increased from 2.30L / (m2h) of the original membrane to 4.92L / (m2h), and the retention rate of NaCl was kept at 90L / (m2h). For magnesium chloride / pure water system, the maximum water flux of the composite membrane is 7.24 L / (m2h), and the Js / Jv is about 0.42 g / L. Compared with single-walled carbon nanotubes, multiwalled carbon nanotubes (MWNTs) increase the water flux and obtain lower reverse fluxes. In addition, when the carbon nanotube content in the supporting layer is 0.15, the maximum flux of magnesium chloride / pure water system is 7.15L / (m2h). When carbon nanotubes are added to the supporting layer and modified layer, the maximum water flux of the composite membrane is 8.25L / (m2h) / (m2h) Js-Jv is about 0.03g/ L. Compared with the pure polyamide membrane, the composite forward permeable membrane with carbon nanotubes added in the supporting layer and the modified layer can obtain higher water flux while maintaining its retention rate. Under the operating pressure of 4 bar, the water flux of the composite membrane was 29.33L / (m2h) and the water flux of the pure polyamide membrane was 20.89L / (m2h), and the water flux of the pure polyamide membrane was 20.89L / (m2h). The water flux of the modified membrane was 29.33L / (m2h), and the rejection rate of the modified membrane was 41L / (m2h), while the water flux of the pure polyamide membrane was 20.89L / (m2h). The antifouling ability of the composite membrane was obviously higher than that of the pure polyamide membrane after three fouling, cleaning and recovery cycles. The recovery rate of water flux and nanofiltration flux was 80.1% and 51.5% respectively for the composite membrane with 0.05% addition in the modified layer, and 73.4% and 35.9% for the pure polyamide membrane, respectively.
【學(xué)位授予單位】：中國(guó)海洋大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：TQ051.893

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1 王蒞;含碳納米管TFN膜的制備與性能測(cè)試[D];中國(guó)海洋大學(xué);2015年

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本文編號(hào)：2075705