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采用两步超滤法对出芽短梗霉发酵产生的聚苹果酸进行分离与提取.发酵液经离心去除菌体后,先采用截留相对分子质量为30 000的超滤膜除去多糖及大分子杂质,接着采用截留相对分子质量为1 000的超滤膜对料液进行浓缩并除去小分子杂质,浓缩液经有机溶剂沉淀和冷冻干燥获得聚苹果酸.采取单因素实验法优化了超滤条件,结果表明:离心除菌后的发酵上清液稀释4倍,跨膜压差0.075 MPa,控制料液pH--6、温度35℃,使用相对分子质量30 000超滤膜稀释超滤1次,分子量1 000超滤膜浓缩4倍后,经甲醇沉淀和冷冻干燥,PMLA的纯度达到82.3%,PMLA的提取收率为57.56%. 相似文献
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《中国新技术新产品》2016,(10)
本文以煤矿矸石电厂中的化学除盐水实验工程为研究对象,研究并分析了超滤装置的工艺和运行模式,并且对超滤装置运行处理中膜污染产生的原因和膜污染类型进行研究分析,根据研究结果提出解决膜污染的化学清洗方案和清洗控制的参数,从而为电厂用水超滤处理工艺的运行和维护提供更坚实的依据。 相似文献
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集成膜过程污水深度处理工艺 总被引:3,自引:2,他引:1
介绍了集成膜过程及其在污水深度处理方面的应用.集成膜过程是将超遽/微遽与反渗透(或纳滤)相结合,形成能够满足各种回用目的的污水深度处理集成工艺.PVDF、PP、PE、PES等超滤/微滤膜,抗污染反渗透复合膜具有化学稳定性高、耐污染、装填密度高等特点,适宜于规模化污水处理.污水处理用超滤/微滤膜以中空纤维为主,系统技术采用了低压运行、频繁(气水、透过液)反冲、气水冲洗等抗污染工艺,能够维持稳定的通量、运行维护费用较低、产水质量稳定.二级出水的集成膜系统工艺已成熟并得以广泛推广,针对原废水的集成膜工艺(膜生物反应器 反渗透)还需要进一步的工程化研究. 相似文献
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超滤过程中操作条件的优化 总被引:9,自引:1,他引:8
超滤过程中操作条件的优化对于发挥超滤的优势是至关重要的,本文以经过预处理后的红霉素板框滤液为处理对象,利用外压式中空纤维膜对其进行超滤,对操作压力、膜面速度、浓缩比,温度等操作条件进行了优化。这些优化方法具有普适性,对其它体系超滤操作具有指导作用。 相似文献
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细胞对硅橡胶复合膜渗透蒸发分离性能的影响 总被引:4,自引:0,他引:4
利用自制的硅橡胶复合膜对乙醇-水模型溶液、含有干酵母的乙醇-水模型溶液、以及实际发酵液进行渗透蒸发分离乙醇实验,研究了细胞对膜性能的影响、结果表明:与纯乙醇模型溶液的分离相比,膜对含有干酵母的乙醇-水模型溶液、真实发酵液的分离表现出更好的性能,显示细胞的存在和活动对膜传质有一定的促进作用.连续发酵过程中,在一定的细胞浓度下(10g/L),硅橡胶膜维持了长期稳定的分离性能;产品乙醇的有效分离降低了其对酵母细胞的抑制作用,使沉积在膜面上的细胞层促进了膜的分离性能;但提高细胞浓度(15g/L)后却因更厚的细胞层的堆积造成膜面传递状况劣化,使膜性能下降.因此发酵液中的细胞浓度、膜面上的细胞沉积以及膜性能之间存在一种最佳的相互促进和搭配关系. 相似文献
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讨论了影响AOT/异辛烷反胶团体系萃取嗜热芽孢杆菌HS08发酵液中耐高温中性蛋白酶的因素.实验结果表明,AOT/异辛烷反胶团在很短的时间内能达到萃取平衡,100 mmol.L-1NaCl的离子强度有助于蛋白酶的反胶团萃取.在50 mmol.L-1AOT、pH4.5、100 mmol.L-1NaCl、油水相体积比为1的条件下萃取5 min能达到80%以上的酶活力回收率. 相似文献
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Microchip dialysis of proteins using in situ photopatterned nanoporous polymer membranes 总被引:1,自引:0,他引:1
Chip-level integration of microdialysis membranes is described using a novel method for in situ photopatterning of porous polymer features. Rapid and inexpensive fabrication of nanoporous microdialysis membranes in microchips is achieved using a phase separation polymerization technique with a shaped UV laser beam. By controlling the phase separation process, the molecular weight cutoffs of the membranes can be engineered for different applications. Counterflow dialysis is used to demonstrate extraction of low molecular weight analytes from a sample stream, using two different molecular weight cutoff (MWCO) membranes; the first one with MWCO below 5700 for desalting protein samples, and the second one with a higher MWCO for size-based fractionation of proteins. Modeling based on a simple control volume analysis on the microdialysis system is consistent with measured concentration profiles, indicating both that membrane properties are uniform, well-defined, and reproducible and that diffusion of subcutoff analytes through the membrane is rapid. 相似文献
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An automated approach for rapid on-line monitoring of the solid and liquid phases present in bioprocesses based on mid-IR Fourier transform spectrometry is introduced. The principles of this new approach are presented using the example of the quantitative and qualitative analysis of poly(beta-hydroxybutyric acid) (PHB) accumulated in living bacterial cells as well as dissolved glucose during two 27-h fermentation processes. FT-IR spectra were recorded on-line using a diamond-attenuated total reflection (ATR) cell connected to the fermentation broth by means of a computer-controlled flow system. For calibration of the FT-IR method, standard reference analysis procedures for PHB (gas chromatography) and glucose (HPLC) were used. While pumping the fermentation broth through the flow cell, the recorded spectra corresponded to the fermentation solution, which allowed the determination of glucose in a range from 3.8 to -10.3 g/L. Upon stopping the flow, the cells settled on the ATR surface, and the thus recorded spectra enabled the determination of the intracellular PHB content of Escherichia coli in a range from 0.005 to 0.766 g/L. Errors of cross-validation of 0.264 g/L for glucose and 0.037 g/L for PHB were obtained. Application of one PLS calibration model to another fermentation was possible with prediction errors of 0.493 g/L for glucose and 0.105 g/L for PHB. Furthermore, from the position and shape of the PHB carbonyl band, it could be concluded that the PHB granules inside the E. coli are predominantly amorphous. 相似文献
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金属膜在1,3-丙二醇发酵液预处理中的应用 总被引:1,自引:0,他引:1
考察了1,3-丙二醇发酵液金属膜过滤在不同浓缩比下的拟稳定通量、黏度及湿固含量变化,在此基础上初步探讨了膜的污染机理,提出了有效的膜清洗方法.结果表明:50 nm的膜适用于1,3-丙二醇发酵液的膜过滤,按料液体积35%,加入去离子水、浓缩倍率在9左右时回收率达到95%.膜污染的主要来源是蛋白,有效的化学清洗方法是:用质量分数为1%NaOH和0.05%EDTA混合溶液清洗膜30 min后,再以0.5%HNO3溶液清洗5 min,膜通量可迅速恢复. 相似文献
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建立可快速准确测定玫瑰孢链霉菌发酵液中达托霉素含量的RRLC方法。采用高分离度快速液相色谱(RRLC)Agilent 1200 series,色谱柱:Aglient XDB C18,1.8u,4.6*50mm。流动相:0.1%三氟乙酸水溶液:乙腈=64:36,检测波长为214 nm,柱温为30℃。结果:达托霉素浓度范围在25~500ug/ml线性良好,相关系数为0.9989;测得发酵液样品的平均回收率为101.7%,RSD为0.63%。结论:方法准确可靠,可以用于达托霉素发酵过程的含量测定。 相似文献