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1.
Application of ultrafiltration, nanofiltration, reverse osmosis, membrane distillation, and integrated membrane processes for the preparation of process water from natural water or industrial effluents was investigated. A two-stage reverse osmosis plant enabled almost complete removal of solutes from the feed water. High-purity water was prepared using the membrane distillation. However, during this process a rapid membrane fouling and permeate flux decline was observed when the tap water was used as a feed. The precipitation of deposit in the modules was limited by the separation of sparingly soluble salts from the feed water in the nanofiltration. The combined reverse osmosis—membrane distillation process prevented the formation of salt deposits on the membranes employed for the membrane distillation. Ultrafiltration was found to be very effective removing trace amounts of oil from the feed water. Then the ultrafiltration permeate was used for feeding of the remaining membrane modules resulting in the total removal of oil residue contamination. The ultrafiltration allowed producing process water directly from the industrial effluents containing petroleum derivatives. Presented at the 33rd International Conference of the Slovak Society of Chemical Engineering, Tatranské Matliare, 22–26 May 2006.  相似文献   

2.
邱长泉  平郑骅  张力恒 《化学学报》2005,63(20):1906-1912
酚酞基聚芳醚酮(PEK-C)超滤膜的表面通过紫外辐照接枝丙烯酸(AA)可以制备对II价盐有很好截留率的亲水性纳滤膜. FTIR-ATR、表面接触角、SEM和AFM的研究结果表明, 在接枝单体溶液中加入异丙醇(i-PrOH)作为链转移剂并不影响AA在PEK-C超滤膜表面的接枝反应. 得到的改性膜同样具有优良的纳滤性能. 与不加i-PrOH的AA改性膜相比, 新合成的膜有较高的滤出液通量, 该膜对盐离子的截留率虽有所降低, 但可以通过增加接枝反应时间和辐照光源的强度来提高. i-PrOH的浓度对膜的分离性能的影响很大, 在低浓度时, 改性膜对离子的截留率会有所下降, 继续提高i-PrOH的浓度, 膜的截留率不再变化而滤出液通量会有成倍的增加, 表明链转移剂的存在可能会提高膜的接枝密度, 增加膜的表面电荷, 使膜对离子的截留率保持不变.  相似文献   

3.
高分子纳滤膜的研究及进展   总被引:5,自引:0,他引:5  
对高分子纳滤膜的发展背景以及国内外在这一领域的研究的研究进展作了详细的介绍。  相似文献   

4.
膜性能;含二氮杂萘酮结构聚芳酰胺超滤膜的研制  相似文献   

5.
PVDF/PAN共混超滤膜   总被引:11,自引:0,他引:11  
尹秀丽  宋艳秋 《应用化学》1997,14(5):112-114
PVDF/PAN共混超滤膜尹秀丽*宋艳秋(天津纺织工学院材料科学系天津300160)关键词聚偏氟乙烯,聚丙烯腈,共混,超滤膜1996-11-20收稿,1997-05-07修回共混是改变高分子材料性能的重要手段,已发现用聚合物共混的方法能制得性能优异的...  相似文献   

6.
储伟  A.Larbot  L Cot  谢在库  陈庆龄 《催化学报》2000,21(5):479-480
用溶胶-凝胶法成功地研制了钴铝系尖晶石膜,并用扫描电镜、粘度测定及超滤测试等方法对薄膜进行了表征,此类尖晶石超滤膜的厚度为1.2~2.5um,平均水透量为40L/(m^2.MPa.h)。  相似文献   

7.
采用界面聚合法制备聚醚砜(PES)中空纤维复合纳滤(NF)膜,讨论了制备条件对PES中空纤维复合NF膜性能的影响。实验结果表明,聚合反应时间、均苯三甲酰氯浓度、哌嗪浓度和酸吸收剂三乙胺浓度对复合NF膜性能有显著影响,同时二次反应能够提高复合NF膜的截留率,对2g/L的Na2SO4截留率可达到99.2%。  相似文献   

8.
To separate small molecules from the solvent with high permeability and selectivity, the membrane process is thought to be highly effective with much lower energy consumption when compared to the traditional thermal‐based separation process. To achieve high solvent permeance, a sub‐10 nm thick polyamide nanofiltration membrane was synthesized through interfacial polymerization of ethidium bromide (EtBr) and trimesoyl chloride (TMC). Thanks to the extremely low solubility of the EtBr monomer in the organic phase, the polymerization process was strictly limited at the interface of the water and hexane, leading to an ultrathin polyamide membrane with a thickness down to sub‐10 nm. When used in nanofiltration, these ultrathin membranes display ultrafast water permeation of 40 liter per square meter per hour per bar (L m?2 h?1 bar?1), and a high Congo red rejection rate of 93 %. This work demonstrates a new route to synthesize ultrathin polyamide membranes by the traditional interfacial polymerization.  相似文献   

9.
聚醚砜超滤膜的结构与性能   总被引:2,自引:0,他引:2  
膜结构;大空腔;聚醚砜超滤膜的结构与性能  相似文献   

10.
Membrane bioprocesses for the denitrification of drinking water supplies   总被引:7,自引:0,他引:7  
A membrane bioreactor (MBR) system, consisting of a bioreactor coupled to a hollow fiber ultrafiltration membrane module, has been developed at the Centre International de Recherche sur l'Eau et l'Environnement (CIRSEE). This process combines the advantages of biological conversion of nitrate to nitrogen with that of hollow fiber ultrafiltration technology to produce high quality drinking water. The influence of several parameters, both biological and hydraulic, on the overall performance of the process has been investigated. With adequate membrane backwashing frequency an crossflow velocity, we were able to obtain, and to maintain for more than two months, a net permeate flow rate of over 100 1-hr−1-m−2. It has also been found that such a high permeate flow rate was not detrimental to the overall denitrification process, since permeate nitrate and nitrite concentration remained below 20 and 0.1 mg-l−1, respectively, for a nitrate volumetric loading rate of 2.8 kg-m−3-day−1 at a hydraulic retention time of either 60 or 30 minutes.  相似文献   

11.
聚酰亚胺微孔膜疏水化用于膜蒸馏   总被引:5,自引:0,他引:5  
采用聚合物表面涂覆改性的方法,将疏水性聚合物硅橡胶涂覆在聚酰亚胺亲水微孔膜上,制得了具有良好膜蒸馏性能的聚酰亚胺疏水微孔复合膜。研究了涂覆工艺条件对所得聚酰亚胺疏水微孔复合膜的膜蒸馏性能的影响。结果表明,控制适当工艺条件可制得具有高膜蒸馏通量的聚酰亚胺微孔复合膜,其透过系数可达2.17×10-3kg/m2·h·Pa。该改性聚酰亚胺疏水微孔复合膜使用37d后,截留率仍保持在99.5%以上,具有较长使用寿命。  相似文献   

12.
膜面结垢是纳滤(NF)膜盐水溶液软化过程中遇到的最主要问题之一。尽管已有大量的研究者对NF膜面结垢趋势预测和膜面污染物形貌的先进科学表征进行了深入广泛的研究,但对NF膜面动态结垢机制和过程还没有系统的报道。本文详细描述了包括膜阻力、浓差极化阻力、滤饼层阻力和膜孔堵塞阻力在内的NF膜结垢阻力理论模型;综述了包括膜面浓差极化、构晶离子成核和膜面结晶沉淀的NF膜面动态结垢过程的研究进展,重点阐述了表面结晶和主体结晶两种NF膜面结晶生长机制的研究概况,并展望了NF膜面结垢机理的研究前景。  相似文献   

13.
研究了以壳聚糖为基准物、浊度法测定超滤膜截留率的方法。以氢氧化钠为沉淀剂,用浊度法分别对6种不同相对分子质量的壳聚糖浓度进行检测,探讨了壳聚糖相对分子质量与氢氧化钠浓度等因素对浊度的影响。结果表明,壳聚糖含量在25~1 000 mg/L范围内与浊度呈现良好的线性关系,线性相关系数r~2≥0.996,检出限在2.1~4.8mg/L之间,样品加标回收率为82.1%~122%。测量结果的相对标准偏差为0.75%~8.7%(n=6)。该法快速、简便,可为超滤膜研究、生产、改性及应用等提供理论指导。  相似文献   

14.
Water flux and hydrophobic durability play important roles in membrane distillation(MD) applications. Compared with the method of adsorbing nanoparticles by electrostatic adsorption, the surface roughness constructed by chemical bonding is more conducive to the performance of membrane. This paper reports a facile approach to fabricating superhydrophobic fluoroalkyl silane/polydimethylsiloxane@FeOOH@stabilized polyacrylonitrile(FAS/PDMS@FeOOH@SPAN) nanofibrous membrane (NFM) with outstanding hierarchical structures, aiming to achieve efficient and stable performance in MD. Electrospun polyacrylonitrile(PAN) membrane after peroxidation was chosen as the base membrane, followed by in-situ synthesis of iron oxyhydroxide and liquid-phase silanization. We tested the characteristics of FAS/PDMS@FeOOH@SPAN NFM in each preparation stage and its performance in direct contact membrane distillation(DCMD). The chemical bond between iron oxyhydroxide and the membrane is stronger, making the rough structure steady and dense. The FAS/PDMS@FeOOH@SPAN NFM exhibited a water contact angle of 155.4° and excellent hydrophobicity towards different pollutants. Besides, it showed satisfied properties with a water flux of 24.7 L·m-2·h-1, a high salts rejection of ca. 100% and an extended-term stability in DCMD using hypersaline water(10%, mass ratio). It is believed that this novel study proposes a universal and efficient method to fabricate a superhydrophobic surface and has great potential for high-salinity wastewater treatment in MD.  相似文献   

15.
In this article, the extraction of arsenic(V) from water by means of emulsion liquid membrane is investigated. The influence of operating factors such as stirring speed, concentration of sulfuric acid in the external aqueous phase, concentration of sodium sulfate in internal stripping phase, and concentration of carrier in the membrane phase on the extraction efficiency are investigated and their optimum values, which provide the maximum recovery of arsenic, are determined. Taguchi experimental design is used in order to reduce the number of experiments. The optimum amounts for the extraction of arsenic from water, based on the results, are: stirring speed, 500 rpm; concentration of sulfuric acid in the feed, 1.5 g mol/lit; concentration of reagent in internal phase, 1.5 g mol/lit; and concentration of carrier in 3 ml kerosene which is added to the membrane phase, 0.1 g mol/lit.  相似文献   

16.
结合膜的形态结构研究了以 LiCl为添加剂制得的疏水 PVDF膜的膜蒸馏性能。与来用水溶液高分子添加剂制得的PVDF微孔膜相比,膜蒸馏性能有了较大提高,尤其具有更高的截留率。制得的微孔膜的蒸馏通量已接近商品膜的膜蒸馏通量,表明以LiCl为添加剂制得的PVDF疏水微孔膜是一种适用于膜蒸馏的较理想的疏水微孔膜。  相似文献   

17.
以新型耐高温工程塑料一含酚酞侧基的聚芳醚砜(PES-C)为膜材料,N,N-二甲基乙酰胺(DMAc)为溶剂,通过改变铸膜液中添加荆草酸的含量,采用相转化法在平板刮膜机上制备了一系列超滤膜,考察了添加荆草酸含量对铸膜液粘度、凝胶速度、膜性能和结构的影响,研究了PES-C/DMAC体系中添加荆草酸作用的规律。  相似文献   

18.
乳化液膜清除未结合胆红素   总被引:2,自引:0,他引:2  
高未结合胆红素症 (Hyperbilirubinemia)是新生儿常见疾病 .胆红素在血液中的浓度过高 ,会伤害婴儿的大脑 (核黄疸 ) [1].肝昏迷患者的症状与胆红素在血液中含量过高也有直接关系 ,迅速有效地将其清除可使患者症状缓解[2 ],迄今为止 ,清除胆红素的研究主要集中在以吸附剂吸附为基础的血液灌流方法 ,所用的吸附剂主要有活性炭和大孔吸附树脂 ,活性炭的吸附选择性和血液相容性都比较差 ;大孔吸附树脂的吸附选择性和血液相容性等方面有待进一步提高[3],特别是在吸附未结合胆红素时 ,清除率低、清除速度慢 ,难以满足临床方面…  相似文献   

19.
Polysulphone (PS) was chemically modified by acrylation-amination and by chloromethylation-amination, respectively. An ultrafiltration membrane of chemically modified polysulphone (CMPS) was prepared by the phase inversion method. Trypsin was then covalently bonded onto the CMPS membrane by diazotization. The activity of immobilized trypsin reaches up to 10200 U/g; 15 mg trypsin was immobilized on 1 g CMPS membrane. Separation of soybean trypsin inhibitor was carried out on the affinity membrane, yielding 6.5 mg pure trypsin inhibitor in one run. The enzyme membrane has good activity and stability.  相似文献   

20.
田苗苗  李雪梅  殷勇  何涛  刘金盾 《化学进展》2015,27(8):1033-1041
超疏水材料具有超高的憎水性和自清洁特性,因而在解决材料的润湿和污染方面具有广泛的应用前景。膜蒸馏是一种以多孔疏水膜两侧蒸汽压差为推动力的膜分离过程,是脱盐和水回用中的重要技术。然而膜润湿和污染问题是导致膜蒸馏过程出水品质下降和应用过程稳定性差的关键。本文以膜蒸馏过程为背景,系统介绍了蒸馏过程的发展状况和超疏水膜材料的制备方法,以及超疏水膜在膜蒸馏中的应用,探讨了超疏水膜材料在膜蒸馏过程中的优势,同时指出了其不足和可能的解决方法,以期为膜蒸馏材料的发展提供研究方向和思路。  相似文献   

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