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介绍了在混合醇萃取前,引入超滤-纳滤组合膜分离技术对板框过滤后的林可霉素发酵液进行提纯和浓缩的小试结果:碱化料液的膜分离效果优于未碱化料液;对不同材料(PES、PS、PA)和相对截留分子质量的超滤和纳滤膜的筛选结果表明,PES-10和NF-270膜在膜通量和林可霉素收率、杂质去除等方面优于其他的膜,为最佳选择;超滤-纳滤后再进行萃取,不但混合醇的用量因料液体积减小而相应减少,并且萃取效率和产品收率都得到提高,当纳滤浓缩倍数为1.28时,一次萃取率和总收率分别比原来无超滤-纳滤时增加了4.3%和3.4%,所得萃取液的色度也较低. 相似文献
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纳滤膜技术在庆大霉素B浓缩中的应用 总被引:3,自引:0,他引:3
阐述了纳滤膜对庆大霉素B溶液的浓缩性能。通过实验得到了时间、浓缩倍数、压力等因素对膜通量的影响,并在此基础上建立了一套每天处理10 m3物料的进口纳滤膜浓缩系统,该系统在8小时内将10 m3物料浓缩50倍,最终物料体积为200 L,浓缩液的效价达十万以上,对物料的收率高于98%,效果明显。 相似文献
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《水处理技术》2014,(7)
用间苯二胺作为水相第二单体,研究了微量间苯二胺对聚哌嗪酰胺复合纳滤膜性能的影响。间苯二胺添加质量分数为0~0.05%,研究了该变量对纳滤膜盐截留率、水通量、表面形貌、水接触角的影响。结果表明,随着微量间苯二胺添加,纳滤膜对氯化钠的截留性能明显上升(34%至90%),水通量明显下降(112 L/(m2·h)至23 L/(m2·h)),膜亲水性下降。X射线光电子能谱结果表明,微量间苯二胺的添加,使得复合层交联度上升,从而进一步引起上述膜性能变化。因此,在纳滤膜生产中,微量间苯二胺可以作为水相的第二单体调控纳滤膜的性能,同时应避免间苯二胺污染引起的膜性能波动。 相似文献
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运用膜技术对荷叶黄酮提取液进行纯化.实验分别采用微滤膜和超滤膜对荷叶黄酮提取液进行初步纯化,研究表明孔径为50 nm的微滤膜Ⅱ对荷叶黄酮提取液有较好的除杂效果,黄酮透过率为97.4%,平均通量为186.7 L×h-1×m-2,且运行稳定;采用纳滤膜和反渗透膜对微滤膜的滤液进行浓缩,研究表明,纳滤膜在浓缩过程中能去除部分盐分等小分子物质,进一步纯化了黄酮溶液,纳滤膜平均通量为32.8L×h-1×m-2,透过率0%. 相似文献
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采用疏水聚四氟乙烯(PTFE)中空纤维膜对垃圾渗滤液反渗透浓水进行真空膜蒸馏(VMD)试验,研究了曝气量、原液温度、冷侧真空度和浓缩倍数等对产水通量、COD、BOD5、氨氮含量、电导率、色度和pH的影响。结果表明,曝气可提高产水通量,当曝气量超过4 m3/(h.m2)时,产水通量趋于稳定;随着原水温度和真空度的提高,产水通量显著增加;浓缩倍数增大会降低产水通量,浓缩4倍后产水通量急剧下降。试验最大产水通量为8.38 kg/(h.m2),产水COD≤100 mg/L,BOD5≤30 mg/L,NH3-N的质量浓度≤25 mg/L,色度小于40度,电导率≤60μS/cm。 相似文献
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Saurabh C. Singh 《分离科学与技术》2017,52(14):2252-2261
The present work aimed to study the performance of ultrafiltration (UF) membranes for hemicelluloses separation, from a caustic-containing highly alkaline, cellulose purification solvent stream of viscose rayon production process, and to understand the membrane behaviour, effect of multiple use cycle, identify potential performance drawbacks and propose possible solutions. Screening experiments showed that an UF membrane with a nominal molecular weight cut-off value of 3 kDa can be used to separate hemicelluloses from alkaline process stream. UF membrane was found to be prone to performance deterioration with time due to fouling. Higher feed temperature helped in improving the membrane flux values while maintaining hemicelluloses retention. 相似文献
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电渗析-超滤耦合技术(EDUF)是一项用于分离带电有机物的新型技术,用超滤膜替换一部分离子交换膜,或将超滤膜嵌入到传统电渗析器中,从而形成一种超滤与电渗析内部结合的新型分离技术。该技术一方面利用超滤膜的孔径差异性分离不同分子量的带电有机物,另一方面利用电驱动原理克服压力驱动式超滤膜的膜污染问题,在营养食品、生物制药等领域用于分离提纯活性有机物组分,展示出了良好的应用优势。本文聚焦于电渗析-超滤耦合技术的产生和发展,详细介绍了该技术的技术原理及应用优势,重点阐述了影响其分离效率的主要因素,包括pH、超滤膜切割分子量(MWCO)、电场强度、膜对结构等。最后,从提高分离效率、降低系统能耗、超滤膜材质、水解液预处理、系统泄漏等角度提出了未来的研究方向,为该技术的研究和应用提供指导。 相似文献
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Membrane fouling is one of the major obstacles for reaching a high flux over a prolonged period of ultrafiltration (UF) process. In this study, a sulfonated-polyethersulfone (SPES)/nano-TiO2 composite UF membrane with good anti-fouling performance was fabricated by phase inversion and self-assembly methods. The TiO2 nanoparticle self-assembly on the SPES membrane surface was confirmed by X-ray photoelectron spectroscopy (XPS) and FT-IR spectrometer. The morphology and hydrophilicity were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM) and contact angle goniometer, respectively. The anti-fouling mechanism of composite UF membrane was discussed through the analysis of the micro-structure and component of UF membrane surface. The results showed that the TiO2 content and the micro-structure of the composite UF membrane surface had great influence on the separation and anti-fouling performance. 相似文献
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The objective of this study is to investigate a combination of ion exchange membranes and free-flow isoelectric focusing (FFIEF) technology for high-selectivity and high-flux protein separation, in which ion exchange membranes are used as the separation media. An FFIEF device has been designed and extensive experiments have been conducted to prove its effectiveness in enhancing the protein separation performance. Three types of membranes were employed in this work and they were commercial microfiltration (MF) ion exchange membranes, commercial neutral UF cellulose membranes, and home-made ultrafiltration sulfonated polysulfone (UF SPSf) ion exchange membranes. The protein separation results show that the home-made UF SPSf membranes have the superior selectivity and flux to other membranes. This is due to the fact that a stable pH gradient across the membranes as well as the interaction between the protein molecules and membrane surface plays an important role in the high-performance protein separation. By applying a semi-batch separation process and optimizing various experimental conditions, a high-purity (>90%) and concentrated target protein is obtained at the permeation side of the home-made UF SPSf membranes with a high flux. 相似文献
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凝固浴处理对聚氨基葡糖超滤膜分离性能的影响 总被引:2,自引:0,他引:2
采用凝固浴凝胶工艺处理聚氨基葡糖超滤膜,实验结果表明,经凝固浴处理后,聚氨基葡糖超滤膜对酸性红B溶液的截留率提高了83.7%;凝固浴的温度、凝固剂的浓度、凝固时间等参数对聚氨基葡糖超滤膜的截留率、渗透通量和孔结构均有一定的影响,选择适当的处理条件可提高膜的分离效率. 相似文献
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Yi He Guangming Li Hua Wang Zhuwu Jiang Jianfu Zhao Hexiang Su Qunying Huang 《Chemical Engineering and Processing: Process Intensification》2010
The conventional process of Reactive Brilliant Blue KN-R production is low purity, labor intensive, inconsistent in the production quality and also causes pollution. The improved process based on membrane technology still generates large volume of effluent though with low pollutants. In this paper, a two-stage membrane separation process is introduced to resolve these shortcomings, in which the first stage is used for diafiltration and concentration of dye solution, and the second is to recover the dye and salt water from the produced permeate. Comparing results from one ultrafiltration (UF) membrane (GH) and four nanofiltration (NF) membranes (AFC40, DL, CA865 and MPT-31), UF membrane ES404 showed the same dye rejection, higher permeate flux and lower sodium sulfate rejection. In the diafiltration and concentration stage, pre-concentration and constant volume diafiltration had the best salt permeability as compared to constant volume diafiltration and post-concentration in addition to variable volume diafiltration. In the dye and salt water recovery, membrane ES404 had the same dye rejection, but higher permeate flux and lower sodium sulfate rejection as compared to membrane GH. The proposed two-stage membrane separation process offers the advantages of high-purity, less labor intensive, consistent in production quality and less pollution. 相似文献
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CO2作为一种天然制冷剂在微通道内应用具有很大的换热优势,然而由于微尺度效应及其物性,在低干度区容易发生干涸,严重影响换热效果。为研究微细通道内CO2流动沸腾换热与干涸特性,搭建了相应实验装置,对内径分别为1mm、2mm、3mm以及内表面粗糙度为16μm的不锈钢管,在CO2制冷剂热流密度2~34kW/m2、质量流率50~1350kg/(m2·s)、饱和温度-10~15℃下进行换热性能与干涸实验对比研究。结果表明:常规管径换热特性在微细通道内不再适用;热流密度的增加对于强化核态沸腾换热具有显著影响,高于临界热流密度(critical heat flux,CHF)则发生干涸;质量流率对于核态沸腾区换热系数的影响则较小;不同饱和温度时换热特性有所不同,高饱和温度下换热系数随其升高而提高,低饱和温度下则相反;干涸过程对总换热系数的影响占34%。研究结论为CO2微通道换热器的研究开发提供理论依据。 相似文献