胶州湾海水纳滤软化的研究

采用超滤-纳滤膜集成膜技术，进行了胶州湾海水纳滤软化现场试验，筛选了纳滤膜，考察了料液流量、操作压力对纳滤膜元件运行效果的影响，评价了纳滤作为海水淡化预处理对海水中主要离子的截留效果，并进行了短期试验。结果表明超滤-纳滤膜集成技术可为淡化系统提供优质的软化水，为胶州湾地区膜法海水淡化奠定了基础。     

纳滤浓缩回收高含磷废水

采用商品纳滤膜NF90浓缩回收高含磷废水,考察了预处理、pH、跨膜压力和浓缩倍数对纳滤浓缩回收含磷废水效果的影响。结果表明,利用氢氧化钠调节废水至pH=5时,固体去除率为64.2%,电导率降低60.3%。纳滤膜除磷技术的优化工艺条件为:料液pH=5,操作压力3 MPa,此条件下纳滤膜可长时间保持较高的通量。料液浓缩5倍时,TP的截留率为91.7%,脱盐率为90.7%。     

应用膜分离技术改进林可霉素提炼工艺

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.     

葛根素的提取与膜分离研究

采用紫外—可见分光光度计测量葛根素的含量,采取乙醇回流水浴提取,通过单因素法和正交试验分别研究提取时间、提取温度、乙醇的浓度、料液比四个因素对葛根素提取的影响。纯化部分主要依靠膜分离技术对提取液进行微滤、超滤、纳滤处理,通过对通量与时间、压力等因素关系的研究,得到合适的膜分离操作工艺条件。     

对纳滤膜分离净化湿法磷酸溶液影响因素的研究

选择NP010和NP030两种纳滤膜对含MgSO_4、Fe_2(SO_4)_3、Al_2(SO_4)_3的磷酸溶液进行分离净化试验,考察了盐含量、操作压力、料液温度等对纳滤膜分离性能的影响。结果表明:随盐含量的增大,纳滤膜的通量减小,其对盐的截留率亦下降;随操作压力的增大,纳滤膜的通量增大,截留率也随之增大,但在压力较高时,截留率增大趋势不明显;料液温度上升,纳滤膜的通量上升,截留率下降;在不同盐含量、操作压力、料液温度的条件下,两种纳滤膜对P_2O_5的截留率均在5%以内。     

大蒜素提取液纳滤纯化的研究

采用乙醇提取方法提取大蒜素,并进行纯化。主要考察纳滤前后大蒜液的变化,并通过在不同温度、压力等条件下进行研究,得出最佳纳滤工艺条件是:温度控制在(33±2)℃,操作压力0.6 MPa。发现纳滤纯化可有效除去杂质,产品中大蒜素含量比单纯的乙醇浸提浓缩产品有大幅提高。     

纳滤和反渗透组合回收盐湖提锂尾液中锂的研究

盐湖提锂后的尾液中仍含有大量的锂,直接外排至盐田会造成锂资源的浪费,并且会对盐湖系统造成破坏,而降低提锂尾液中的镁锂比是回收提锂尾液中锂的关键。采用纳滤和反渗透组合工艺成功地回收了提锂尾液中的锂。考察了7种型号的纳滤膜对提锂尾液中镁锂分离的效果,结果表明1号纳滤膜的分离效果最好。以1号纳滤膜为纳滤元件,考察了纳滤膜在不同的过滤压力、实验温度和提锂尾液稀释倍数条件下对提锂尾液中镁锂分离的效果,得到较优操作条件：过滤压力为4 MPa、提锂尾液稀释倍数为6倍、实验温度为35 ℃。以1号纳滤膜为纳滤元件,在较优操作条件下采用二级纳滤对提锂尾液进行镁锂分离,再通过反渗透对富锂液相进行浓缩,得到镁锂质量比为13.8、锂离子质量浓度为0.39 g/L的富锂液相。富锂液相经过浓缩除杂,然后与纯碱反应,可制备电池级碳酸锂。纳滤截留的镁离子含量较高的液相则外排至尾液池,经蒸发浓缩排入盐田再回收利用。     

克林霉素磷酸酯生产工艺中膜浓缩技术的研究

针对克林霉素磷酸酯(CLP)工业生产过程中解吸液的组分特性和目前传统生产技术存在的问题,研究了用膜浓缩替代蒸发浓缩的可行性和实用性,重点考察了膜材质和操作温度、操作压力等对纳滤的分离性能的影响,优化了工艺条件.结果表明,用复合膜、压力在1.5 MPa左右、温度为55℃左右进行纳滤浓缩得到的CLP质量优于传统工艺.     

纳滤膜处理含镍电镀废水的中试研究

采用纳滤膜法对电镀镍漂洗废水及金属镍的在线回用进行中试研究,维持p H、TDS、电导率、温度等条件不变,改变操作条件,研究了操作压力、进水流量、料液浓度、运行时间、产水比对膜分离性能的影响。研究结果表明,增加操作压力、进水流量、料液浓度都可提高Ni2+截留率及浓缩倍数;保持各影响因素恒定运行时,纳滤膜对Ni2+截留率及浓缩倍数随运行时间的延长逐渐增大,稳定运行40 h后接近最大截留率及最大浓缩倍数,截留率达75%左右,浓缩倍数在6.2倍左右;产水比对Ni2+截留率有较大影响,产水比为1∶1、进水流量为6 t/h时,Ni2+截留率为65.7%,浓缩倍数为2.4倍。     

纳滤膜技术浓缩分离含镍离子溶液

采用纳滤膜法对较高浓度含Ni2+离子溶液进行了高倍数浓缩,考察了操作压力、进料液流量、原水Ni2+离子质量浓度和pH等因素对分离过程性能的影响.结果表明,纳滤膜对Ni2+的截留率随操作压力、进料液流量和原水Ni2+质量浓度的增加而增大,膜通量则随进水Ni2+的质量浓度增加而减小.对于Ni2+质量浓度为3900 mg·L-1,pH为3的NiSO4溶液原水,在操作压力1.4MPa条件下,经截留液全循环工艺运行,纳滤淡化出水Ni2+的截留率均保持在99.6%以上,浓缩液中Ni2+质量浓度最高可能达到23 510mg·L-1,浓缩倍数超过6.研究表明,选择适宜的纳滤膜用于重金属废水的高倍数浓缩,实现有价金属的资源化回收具有良好的技术可行性.     

膜分离技术分离纯化泰乐菌素的研究

简要介绍膜分离技术,采用超滤膜、纳滤膜对泰乐菌素发酵液进行脱色除蛋白试验。通过考查该体系膜通量、发酵液浓缩情况及滤液质量等,发现采用膜系统处理泰乐菌素发酵液在工艺、技术上是可行的,比传统过滤方式具备很多优越性。     

Purification and concentration of gluconic acid from an integrated fermentation and membrane process using response surface optimized conditions

A response surface method was used to optimize the purification and concentration of gluconic acid from fermentation broth using an integrated membrane system. Gluconobacter oxydans was used for the bioconversion of the glucose in sugarcane juice to gluconic acid (concentration 45 g·L^-1) with a yield of 0.9 g·g^-1. The optimum operating conditions, such as trans-membrane pressure (TMP), pH, cross-flow rate (CFR) and initial gluconic acid concentration, were determined using response surface methodology. Five different types of polyamide nanofiltration membranes were screened and the best performing one was then used for downstream purification of gluconic acid in a flat sheet cross-flow membrane module. Under the optimum conditions (TMP=12 bar and CFR=400 L·h^-1), this membrane retained more than 85% of the unconverted glucose from the fermentation broth and had a gluconic acid permeation rate of 88% with a flux of 161 L·m^-2·h^-1. Using response surface methods to optimize this green nanofiltration process is an effective way of controlling the production of gluconic acid so that an efficient separation with high flux is obtained.     

超滤技术在生物酶分离中的研究进展

该文综述了超滤技术的原理、分离过程、发酵液的性质以及超滤膜和超滤条件对生物酶超滤性能的影响。并从发酵液的处理、超滤膜和超滤过程的优化三方面出发,对近期提高超滤性能取得的成果进行了总结和讨论。最后指出生物酶超滤技术的未来发展方向有以下几点:超滤数学模型的开发;提高酶的稳定性;超滤膜的改进和开发;超滤工艺的改进。     

纳滤分离提取谷氨酰胺过程的研究

对发酵液中的谷氨酰胺提取进行了采用纳滤膜分离技术的尝试，并对谷氨酰胺和谷氨酸混合溶液的纳滤分离进行了理论分析。研究了不同pH条件下发酵液中谷氨酰胺和谷氨酸在纳滤过程中的透过特性，并考察了纳滤过程中氨基酸的透过特性随压力和浓度的变化。结果表明：当发酵液pH=7，谷氨酰胺浓度为1％时，纳滤膜分离谷氨酰胺的提取总收率可达到65％以上。     

接触氧化沉淀-超滤-纳滤处理引黄水库水中试

开展了生物接触氧化沉淀-超滤-纳滤组合工艺处理引黄水库水的中试,考察组合工艺连续稳定运行条件下除污染效能。结果表明,组合工艺对常规污染物、特征污染物均有良好的去除效果,浊度、TOC、UV254和CODMn等常规污染物去除率分别为95%、90%、90%和85%;总硬度、总碱度、溶解性总固体的去除率分别达到了97%,86%和91%,总脱盐率在95%以上;色氨酸、酪氨酸、SMPs、富里酸、类腐殖酸等荧光类有机物及消毒副产物前质消减率达到了88%和50%以上。组合工艺的除污染效能主要集中在纳滤单元,生物接触氧化沉淀和超滤单元对原水浊度和大分子有机物具有一定的去除效果,能为后续工艺减轻操作压力。定期对超滤、纳滤膜进行清洗可有效恢复工艺各项参数,延长膜工艺使用寿命。     

发酵液的组成对纳滤分离谷氨酰胺的影响

研究了谷氨酰胺发酵液中盐离子对纳滤分离提取谷氨酰铵的作用，系统地考察了操作温度和发酵液组成对纳滤分离透过特性的影响，确定了纳滤分离时发酵液最佳稀释倍数和操作温度. 结果表明，二价阳离子通过改变膜面电荷密度对谷氨酸的透过特性产生很大影响，使其截留率降低了8%. 发酵液中较高浓度的(NH4)2SO4使谷氨酸和谷氨酰胺的截留率和透过通量明显降低，但较高浓度的NH4Cl影响较小，这体现了纳滤膜对不同离子排斥力的差异. 当发酵液稀释至谷氨酰胺浓度为1%，pH调至7时，发酵液中的其它盐离子和残糖因浓度较低而对纳滤分离影响不显著.     

New polymeric membrane nanofiltration for succinate recovery: a comparative study

Bio-based succinic acid recovery from fermentation broth has remained a challenge in the separation industry due the presence of by-products with similar physicochemical properties. In this work, the selective separation of succinate from succinate model solutions and the actual fermentation broth were investigated using newly fabricated polyimide P84 (PI) nanofiltration (NF) membrane and compared with three types of commercial pressure filtration membranes namely NF1, NF2 and NF270. Results show that PI membrane demonstrated comparable inorganic salt rejections performance as the commercial NF membranes of 86% and 99% for NaCl and Na₂SO₄, respectively. However PI shows much lower surface roughness, beneficial in reducing the fouling effect. PI also demonstrated equivalent performance for succinate permeation flux and retention at high concentration as the commercial membranes. PI exhibited high succinate retention (95%) in actual fermentation broth, equivalent to the commercial membranes (92–99%) and also higher selectivity factor (SF) < 0.14 compared to the NF1 membrane, SF < 0.19. Thus the PI membrane could give better succinate recovery against other carboxylates in the fermentation broth than the commercial membranes.     

Clarification of succinic acid fermentation broth by ultrafiltration in succinic acid bio–refinery

BACKGROUND: Succinic acid is an important precursor chemical for the synthesis of high value‐added products. In this work, ultrafiltration was first investigated to clarify succinic acid fermentation broth by integrating fermentation and separation and removal processes of the product in situ. Four different ultrafiltration membranes (PES 100 kDa, PES 30 kDa, PES 10 kDa and RC 10 kDa) were used in this work. RESULTS: Results indicate that ultrafiltration is feasible for clarifying succinic acid fermentation broth. Almost all the microorganism cells (99.6%) were removed from the fermentation broth. Proteins were also removed effectively by all the membranes studied. The removal rate was 79.86% for PES 100 kDa, 86.43% for PES 30 kDa, 86.83% for PES 10 kDa, and 80.06% for the RC 10 kDa. After ultrafiltration, a clearer permeate was obtained compared with that from centrifugation. CONCLUSION: Membranes operating at high flux are always susceptible to rapid fouling. Compared with molecular weight cut‐offs (MWCO), membrane material has a significant influence on the flux. Membrane flux measured in this study shows industrial potential of this technology in treatment of succinic acid fermentation broth. © 2012 Society of Chemical Industry     

Separation characteristics of sodium fusidate in ultrafiltration

The aim of this study is the investigation of the separation characteristics of sodium fusidate by means of ultrafiltration. The influence of several parameters, such as feed concentration, applied transmembrane pressure, pH, ionic strength, temperature and membrane material, on the retention and flux behavior have been investigated. The experiments were performed in a thin channel module, with four different ultrafiltration membranes, in order to choose a membrane with a proper retention and good operating conditions. In addition, the influence of the hydraulic permeability of the membranes, taking into account each experiment and contact time with solutions of sodium fusidate and dextran, was also analyzed in this work. The film theory model was used to estimate the mass transfer coefficient by means of the variation velocity method. The membrane-sodium fusidate interactions were studied by measuring the water flux of the membranes and by using the finely pore model, which combines both the viscous flow and frictional models. The present study gives good insight on the interactions within membrane filtration in the downstream processing of sodium fusidate. However, the situation is often more complex in real fermentation broth, since fermentation media contain hydrophobic or surface active substances which strongly influence the performance of the membrane.