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1.
探索大孔树脂分离技术对中药复方不同药物组合物理化学参数的影响。以黄连解毒汤为实验体系,测定AB—8大孔树脂分离前后该复方不同药物组合原液及醇洗脱液的pH值、电导率、浊度、粘度等指标。黄连解毒汤不同药物组合在AB—8大孔树脂分离前后的pH值、电导率、浊度、粘度等方面表现出不同的变化。大孔树脂分离技术可改变中药复方不同药物组合的物理化学参数。  相似文献   

2.
50味常用中药挥发油的理化性质研究   总被引:2,自引:0,他引:2  
通过考察50味常用中药挥发油的物理化学性质,建立其表征技术体系,探索中药挥发油物理化学性质的规律性。以水蒸气蒸馏法提取50味常用中药中的挥发油,测定其20、40、60~C时的浊度、粘度、电导率、盐度、pH值、密度、表面张力、折光率等指标。结果表明,中药挥发油一般均较澄清、粘度在0—10mPa·S之间,无盐度和电导率,pH值在3.353—6.654之间,为弱酸性,相对密度在0.8557~1.1516之间,表面张力在27.85—50.46N·cm。之间,折光率在1.4475—1.5987之间,这些物理化学参数随温度的变化存在一定的规律性。  相似文献   

3.
研究中药水提液的粘度对无机陶瓷膜微滤中药水提液膜通量的影响及中药水提液在微滤前后粘度变化规律。制备约200种中药(单味及复方)水提液为实验体系,在温度、压力、膜面流速恒定的条件下分别过0.2μmZrO2无机陶瓷膜,测定不同中药水提液的膜稳定通量及微滤前原液、微滤后渗透液、截留液的粘度,并用SPSS对它们的相关性进行分析。结果表明中药水提液的粘度与膜稳定通量有很大的相关性,微滤后渗透液的粘度减小且不同水提液粘度差异性变小,截留液粘度增大、且截留液粘度、粘度变化率与原液粘度呈高度显著线形相关。粘度是影响无机陶瓷膜微滤中药水提液膜通量的关键因素,在中药膜污染的防治过程中可通过提取路线的设计或对药液进行预处理降低药液的粘度从而提高膜通量,减少膜污染。  相似文献   

4.
通过将PES掺入高磺化度的SPEEK进行共混改性,采用流延法制备了一系列不同PES含量的SPEEK/PES共混膜,获得了SPEEK/PES共混膜的离子交换容、含水率、质子电导率等参数,特别测定了在全钒液流电池工作条件下钒(IV)离子渗透率。综合考察发现,当磺化温度为45℃,磺化时间控制为4h,得到SPEEK的DS为55%,掺入10%的PES,此时共混膜的电导率为0.08S/cm,钒(IV)离子渗透率为0.38×10^-6cm2/min,对钒(IV)离子选择性为Nation膜的5倍,含水率为35%,共混膜综合性能最好,基本满足全钒液流电池(VRB)的使用需求。  相似文献   

5.
不同季度渗滤液性质研究   总被引:2,自引:0,他引:2  
用不同孔径的系列膜对不同季度渗滤液进行梯度分离。对分离前后渗滤液的COD、TOC、pH、TP、氨氮、正磷酸盐、色度、浊度和电导率等参数进行了测定,并建立了各参数与不同孔径膜的关系。结果表明:老港填埋场3月份渗滤液比6月份渗滤液污染性强,渗滤液的C:N:P的比分别为1168:232:1和1003:377:1,对于生物处理工艺来说,其C:N:P比例明显失调。同时发现:渗滤液的绝大部分污染物质集中于可溶性部分,而渗滤液中的P主要与大分子的悬浮物和粗胶体结合。在浊度与色度这两指标中,悬浮物和粗胶粒大约贡献一半左右。  相似文献   

6.
由异辛基乙二胺(2-Ethyl-N-hexylethylenediamine,EtHexen)与辛酰基丙氨酸(Octanoylalanine,Octala)合成了鳌合胺型酰基氨基酸类新型质子化离子液体[HEtHex][Octala]。研究了其溶解性、热稳定性(T_d)、熔点(T_m)及吸收CO_2的能力。[HEtHex][Octala]极易溶于水,可达90 wt.%以上,其热分解温度为173.1℃,熔点为32.6℃。配制摩尔比分别为1∶10、1∶15、1∶20及1∶25的[HEtHex][Octala]/水体系,并在30℃下,测定了其吸收CO_2前后体系的pH值、密度(ρ)、粘度(η)及电导率(σ)值。结果显示:随着体系中水的摩尔比的增加,其pH值、密度、粘度值下降、电导率值增大;吸收CO_2后,与吸收CO_2前比较,体系的pH值和电导率降低,密度和粘度增大。  相似文献   

7.
研究了pH值、温度、盐及其浓度变化对溴代十六烷基吡啶/正丁醇,苯/水微乳液体系电导率变化趋势的影响。结论表明,pH值对体系的电导率没有明显影响,50℃以上时,微乳液体系在碱性条件下比在酸性条件下稳定。当体系加入不同盐时,电导率随温度升高、盐浓度的增大而增大;同样条件下,硫酸钠体系的电导率要比氯化钠体系高。  相似文献   

8.
利用椰类混凝剂处理使地表水样澄清。对于浊度为7.43NTU的原水,使用220mg/L的椰油块处理,水的浊度可降低到2.98NTU。对经椰汁处理后的水进行物理化学分析和细菌分析表明处理对温度、pH、电导率没有任何影响,但会稍微增加硬度和高锰酸钾指数。  相似文献   

9.
张平允  李康康  徐超  郎万中 《净水技术》2021,40(1):37-43,87
以PES/DMAc/DEG低临界共溶温度(LCST)体系为铸膜液,利用低临界共溶温度(LCST)的热致相分离(LCST-TIPS,简称RTIPS)法制备PES微孔膜。探究影响PES微孔膜理化性能及其结构的2个主要因素:凝胶浴温度、非溶剂(DEG)/溶剂(DMAc)的质量比。运用扫描电镜(SEM)﹑纯水通量﹑BSA截留率和机械强度表征微孔膜的结构和性能。试验结果表明:随DEG∶DMAc质量比增加,PES/DMAc/DEG体系的相分离温度降低;SEM结果显示,RTIPS法制备的PES微孔膜表面有明显的微孔,断面呈现双连续海绵状结构;当DEG∶DMAc质量比为0.9∶1、凝胶浴温度为80℃时,PES/DMAc/DEG体系制得的PES膜的渗透性能和机械性能最优:纯水通量为1 230 L/(m^2·h),断裂强度为1.95 MPa。PES/DMAc/DEG体系制得的最优性能的PES平板膜MSWDEG-2-80的应用结果显示,其对膜进水中的UV254具有较好的去除效果,且膜出水浊度稳定,为(0.23±0.01) NTU。  相似文献   

10.
针对部队指战员、野外施工作业人员的饮水安全需求,结合野外水处理装置的实际使用环境,确定了适宜的饮用水处理工艺;通过中试试验,优化各工艺参数,研制了一种小型机动水库自洁净化装置。在中试试验中,考察了处理前后色度、浊度、菌落总数、pH、电导率、TDS、溶解氧、总磷、COD_(Cr),温度、流量、压力等水质参数的变化。试验结果表明:一级装置及二级装置出水流量稳定,经过一级装置处理后,色度、浊度、COD_(Cr)、总磷及菌落总数均有明显下降,再经过二级装置处理后,色度、浊度及菌落总数进一步显著下降;而pH、电导率、TDS有微小变化。二级装置出水的色度、浊度、菌落总数、pH、电导率、TDS等水质参数能达到《生活饮用水卫生标准》(GB 5749—2006)的规定。所设计的水库自洁净化设备占地面积小,结构简单,便于机动作业,易于维护。  相似文献   

11.
Blend PES/CA hydrophilic membranes were prepared via a phase-inversion process for oil–water separation. PEG-400 was introduced into the polymer solution in order to enhance phase-inversion and produce high permeability membranes. A gas permeation test was conducted to estimate mean pore size and surface porosity of the membranes. The membranes were characterized in terms of morphology, overall porosity, water contact angle, water flux and hydraulic resistance. A cross-flow separation system was used to evaluate oil–water separation performance of the membranes. From FESEM examination, the prepared PES/CA membrane presented thinner outer skin layer, higher surface porosity with larger pore sizes. The outer surface water contact angle of the prepared membrane significantly decreased when CA was added into the polymer solution. The higher water flux of the PES/CA membrane was related to the higher hydrophilicity and larger pore sizes of the membrane. From oil–water separation test, the PES/CA membrane showed stable oil rejection of 88 % and water flux of 27 l/m2 s after 150 min of the operation. In conclusion, by controlling fabrication parameters a developed membrane structure with high hydrophilicity, high surface porosity and low resistance can be achieved to improve oil rejection and water productivity.  相似文献   

12.
In this study three different types of lithium halides; lithium bromide (LiBr), lithium chloride (LiCl) and lithium fluoride (LiF) were used as additives in the making of polyethersulfone (PES) membranes. The concentration of PES is kept constant at 20 wt.% throughout the study, and the lithium halide concentration is varied in the range of 1-5 wt %. The solvent used is N, N-dimethylformamide and the PES asymmetric membrane was prepared by the dry/wet phase inversion process. Membrane performance was characterized in terms of pure water permeation (PWP), permeation rate (PR) and solute separation of polyethylene glycol (PEG) solution of various molecular weights ranging from 600 to 35,000 Da. The molecular weight cut off (MWCO) and mean pore size distribution were subsequently determined. Results revealed that the 3 wt.% LiBr exhibits the best performance with MWCO at 90% rejection in the range of 2.83 kDa and high flux range of 117.69 L m− 2 h− 1. Hollow fibers spun from the dope solutions containing LiBr revealed that they are capable of treating palm oil mill effluent (POME) with reduction in turbidity, chemical oxygen demand (COD) and biochemical oxygen demand (BOD) of 96.7%, 53.12% and 76.7% respectively.  相似文献   

13.
Effective separation of oil from water is of significant importance globally for various applications such as wastewater treatment, oil spill cleanup, and oil purification. Among the numerous approaches for oil removal, membrane separation is considered one of the most promising approaches due to its selectivity and ease of operation. Electrospinning is a promising technique for producing polymeric membranes with tunable structures with interconnected pores, large surface area, and high porosity. In this study, hydrophobic poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) nanofibrous membranes were electrospun and used for this purpose. The effects of various parameters (e.g., polymer concentration, applied voltage, tip to collector distance, and feed rate) were investigated to find the optimum electrospinning conditions. Further, the electrospun membranes were characterized according to average fiber diameter, morphology, average pore size, and wettability to identify the combinations most likely to succeed in oil–water filtration. The physical–chemical properties of the membranes (i.e., thickness, areal density, porosity, average pore size, water/oil contact angle, hydrostatic pressure head, and oil filtration flux) were studied based on standard test methods. The separation efficiency of eight electrospun membranes with various pore sizes and average fiber diameters were tested for diesel/water mixtures. A linear relation was found between the initial oil flux and the average pore size of the membranes. The maximum oil filtration flux of about 224 L/m2/h, achieving over 75% oil recovery in 10 min, was obtained for the electrospun membrane with the average pore size of 4.5 μm. The membranes were successfully used for eight consecutive oil–water separation cycles without noticeable loss of flux.  相似文献   

14.
膜分离中有机物的特性对去除率的影响研究   总被引:2,自引:0,他引:2  
试验采用ESNA1-2012纳滤膜和ESPA1-2012反渗透膜对有机物进行了分离研究,研究结果表明,在膜分离过程中影响有机物去除率的因素较多,其中有机物的本身特性对其去除率的影响极大;有机物的物理化学特征参数影响是膜与有机物间排斥力的作用,而有机物分子量的相对大小影响则是膜孔机械截留作用的大小。当有机物的分子量小于膜的截留分子量时,有机物的物理化学特征参数成为影响其去除率的主要因素;当有机物的分子量大于膜的截留分子量时,有机物的分子量与其物理化学特征参数共同成为影响其去除率的主要因素。  相似文献   

15.
In order to reduce surface aggregation and enhance the performance of PES membranes, a hydrophilic PES/TEOS HF membrane was developed for the treatment of wastewater containing oil. PES/TEOS was prepared via a sol-gel self assembly and dry–wet spinning method. Silicon dioxide sol was prepared from a mixture of tetraethoxysilane, ethanol, water, and acetic acid (acting as the catalyst). HF hybrid membranes were produced from dope solutions containing polyethersulfone, polyethylene glycol, silicon sol, and NMP. The membranes were characterized by field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), energy-dispersive X-ray spectroscopy (EDX), porosity, fourier transform infrared spectroscopy (FTIR), and contact angle measurements. The composite membranes were successfully used to treat wastewater containing oil and their separation performance were evaluated. The PES/TEOS-2 membrane displayed the best performance, with a permeate flux of 90.937 L/m2 h and an oil retention of 99.98%. In addition, this membrane showed a higher pure water flux of 102.43 L/m2 h as compared to PES-0 and PES/SiO2–1 membranes (87.347 L/m2 h and 91.949 L/m2 h, respectively). The PES/TEOS-2 membrane also presented enhanced antifouling behavior with a FRR and a RFR of 93.33% and 11.22%, respectively. In addition, this membrane displayed excellent long-term recycling properties, making it a desirable candidate for oily wastewater separation applications.  相似文献   

16.
Eleven PES membranes, into which newly synthesized surface-modifying macromolecule (nSMM) was incorporated, were prepared by using the ‘phase inversion technique’ with different preparation conditions to find the effects of membrane casting parameters on the characteristics and performances of the surface modified PES membranes. The membranes so prepared were characterized by solute separation data from ultrafiltration experiments. The results showed that the mean pore size as well as the surface hydrophobicity increased with an increase in evaporation time for the casting solution blended with nSMM (without PVP). When PVP was added into the casting solution, the mean pore size as well as the contact angle decreased while the pure water permeation flux increased. The surface hydrophobicity decreased with an increase in gelation bath temperature.Four membranes were further prepared and subjected to vacuum membrane distillation (VMD). They were characterized by different analytical instruments and pure water permeation test before being used to VMD. The results showed that a distinctive surface layer was formed in nSMM blended PES membranes. It was also found that nSMM blended PES membranes were sufficiently hydrophobic and porous to be used for the separation of an ethanol/water mixture.  相似文献   

17.
Tangential flow filtration of the collagen protein solutions with a molecular weight 12, 14, and 24 kDa is investigated using flat sheet membranes. The effects of tangential ultrafiltration (UF) on the permeate properties using two regenerated celluloses (RCs) and two polyethersulfone (PES) membranes with molecular weight cut-off (MWCO) of 5 and 10 kDa are reported. The permeate and concentrate obtained in the UF experiments are characterized from a physical–chemical point of view by determining the temperature, pH, electrical conductivity, nitrogen content, and protein concentration. In addition, the experimental data are modeled using Hermia's model. The UF experiments demonstrated that permeate flux declined with increasing molecular weight of collagen at constant concentration (1%). Regardless of the molecular weight of collagen, the rejections decrease in the following order: PES 5 kDa > RC5kDa > RC10kDa > PES10kDa. In case of membrane with higher MWCO, the clogging phenomenon is mainly due to the blockage of the internal pores of the membrane than the formation of a polarization layer. Morphologies and characteristics of the membranes are characterized using scanning electron microscopy.  相似文献   

18.
《分离科学与技术》2012,47(15):2089-2104
Abstract

Bed coalescence efficiency of oil separation from formation water was studied on model systems involving 10 real samples of crude oil and its fractions of different characteristics. Oil components were varied and all other parameters were kept constant, and high mineralization water served as the continuous phase. All experiments were realized on a commercial WO/O4 two-stage bed coalescer. Temperature, oil content, and fluid velocity were kept constant for all samples. Model emulsion was dispersed by constant stirring during the experiment to obtain primarily droplets of 20 μm diameter. Correlations for predicting the coalescence efficiency as a function of some physical and chemical oil properties are presented. The investigated oil components ensured a wide span of viscosity, density, and interfacial tension. The influences of mean molecular weight, neutralization number, as well as the contents of n-alkenes, NSO, and aromatics on coalescence efficiency were analyzed. On the basis of the empirical dependences of coalescence efficiency on individual parameters obtained by regression analysis of the data, a general mathematical model was established.  相似文献   

19.
Poly(ether sulfone) (PES) hollow-fiber membrane was prepared via a nonsolvent-induced phase-separation method, and the effect of the addition of the surfactant Tetronic 1307 on the membrane performance and characteristics was investigated. The phase diagram of the PES/N-methyl-2-pyrrolidone (NMP)/water system was clarified. When the polymer solution involved Tetronic 1307, the amount of water required to induce the phase separation decreased, which indicated that Tetronic 1307 was one kind of nonsolvent. The kinetics of phase separation for the PES/NMP/Tetronic 1307 system were studied by light-scattering measurements. With the addition of Tetronic 1307, delayed phase separation was observed, and the structure growth rate decreased. Scanning electron microscopy images for all of the membranes showed the formation of fingerlike macrovoids through the cross section. Membrane surface morphologies were measured by atomic force microscopy. The obtained results indicated that membrane with 7 wt % Tetronic 1307 had higher roughness parameters than original membrane without the addition of surfactant. Ultrafiltration experiment results showed that the addition of Tetronic 1307 brought about an increase in water permeability and decreased the rejection of dextran with a molecular weight of about 10,000. The contact angles of water on the membrane outer surface decreased with the addition of Tetronic 1307. This mean the membrane surface became more hydrophilic. Thus, the addition of Tetronic 1307 was useful for improving the water permeability and for obtaining a hydrophilic membrane surface. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

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