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1.
The facilitated transport of penicillin G from aqueous solutions to the stripping phase through bulk liquid membrane (BLM)
containing TBP in 3% iso-octanol and n-butyl acetate was studied. Na2CO3 solution was used as the stripping phase. Experiments were performed as a function of stirring rate, TBP concentration and
type of diluent in the liquid membrane phase, pH, and initial penicillin G concentration in the feed phase, Na2CO3 concentration in the stripping phase, etc. The results showed that the BLM process could carry out the simultaneous separation
and concentration of penicillin G from dilute aqueous solutions, and arise “up-hill” effect due to the characteristic of non-equilibrium
mass transfer. The diffusion of penicillin G complex in the liquid membrane phase played an important role in BLM process.
The mass transfer mechanism of BLM for this system was also discussed. 相似文献
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以S,S-酒石酸正十二酯和H3BO生成的配合物为手性载体, 通过量热分析结果初步证明该配合物的存在, 采用厚体液膜拆分了普萘洛尔外消旋体. 考察了S,S-酒石酸十二酯浓度和水相pH值对拆分性能的影响, 优化了其拆分操作条件, 同时进行了动力学分析. 得出厚体液膜拆分的一般规律, 即其拆分属于动力学拆分过程, 适当提高手性载体的浓度有利于提高对映单体流量和拆分的立体选择性, 水相pH值对于拆分性能有着重要的影响. 其拆分过程中萃取反应过程为控速步骤, 对映单体的跨膜传递可以用两个串联的准一级不可逆过程进行描述. 相似文献
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Granado-Castro MD Galindo-Riaño MD Domínguez-Lledó FC Díaz-López C García-Vargas M 《Analytical and bioanalytical chemistry》2008,391(3):779-788
The coupled transport of Cu(II), Cd(II) and Ni(II) ions through a bulk liquid membrane (BLM) containing pyridine-2-acetaldehyde
benzoylhydrazone (2-APBH) as carrier dissolved in toluene has been studied. Once the optimal conditions of extraction of each
metal were established, a comparative study of the transport kinetics for these metals was performed by means of a kinetic
model involving two consecutive irreversible first-order reactions. The kinetic parameters (apparent rate constants of the
metal extraction and re-extraction reactions (k
1, k
2), the maximum reduced concentration of the metal in the liquid membrane (), the time of the maximum value of R
o
( t
max) and the maximum entry and exit fluxes of the metal through the liquid membrane ( and ) of the extraction and stripping reactions were evaluated and results showed good agreement between experimental data and
theoretical predictions. Complete transport through the membrane took place according to the following order: Cd(II)>Cu(II)>Ni(II),
with similar kinetic parameters obtained for Cu(II) and Cd(III). The transport behaviour of Ni(II) was different to that of
Cu(II) and Cd(III), probably due to the different stoichiometry of the nickel complex compared to those of the other metal
ions and the different chemical conditions required for its formation. The influence of the sample salinity on the transport
kinetics was studied. k
1 values decreased slightly when the feed solution salinity was increased for Cu(II) and Ni(II), but not for Cd(II). Values
of k
2 were practically unaffected. The proposed BLM was applied to the preconcentration and separation of metal ions (prior to
their determination) in water samples with different saline matrices (CRM, river water and seawater), and good agreement with
the certified values was obtained. 相似文献
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With the gradual depletion of traditional zinc resources, the full use of various non-traditional zinc-containing resources has received intensive attention. However, the efficient recovery of zinc ions with low concentrations remains challenging. Here efficient and continuous recovery of zinc ions in ammoniacal chloride media by a flat supported liquid membrane system is achieved, using Cyanex923 and TBP mixed extractant as the membrane phase. This article discusses the synergistic effect between Aliquat336, Cyanex923 and TBP, the effects of feed pH, total ammonia concentration, Cl− concentration and temperature on Zn(II) transport. 相似文献
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研究了以多孔聚丙烯膜为支撑体,N,N′-二(1-甲基庚基)乙酰胺(N-503)为膜流动载体的苯酚支撑液膜传输行为;用液-液萃取法测定了N-503/煤油体系中苯酚萃合物组成为1∶1,及在相应的条件下萃取常数Ke′x为53.7;考察了料液相的pH值、载体浓度、实验温度、起始浓度以及解析相NaOH的浓度对苯酚传输的影响,并对该体系分离、传输苯酚的最佳条件进行了讨论;从界面化学和扩散传质角度提出了苯酚的传输动力学方程,采用直线斜率法对苯酚在N-503/煤油支撑液膜体系中的扩散层厚度和膜内扩散系数进行了测定,取得满意结果。 相似文献
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Hiroshi Ikeda Akiyuki Matsuhisa Akihiko Ueno 《Journal of inclusion phenomena and macrocyclic chemistry》2002,44(1-4):347-350
A new effective transport system for saccharides through a liquid membranewas constructed. The transport rate of d-ribose in the condition of theliquid membrane with cyclodextrin dimer (2) as a transporter is 2.5 timerlarger than that without the transporter, whereas the transport rate of d-ribosein the condition of the liquid membrane with cyclodextrin monomer (1) isalmost the same as that without the transporter. The transport rate of methyld-glucoside by 2 is over twice than that by 1. The transport rate of d-deoxyribose by 2 is larger than that by 1. 相似文献
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Canan Onac H. Korkmaz Alpoguz Ezgi Akceylan Mustafa Yilmaz 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(10):1013-1021
Chromium(VI) is one of the major toxic elements present in environmental samples. The polymer inclusion membrane (PIM), has been developed to provide metal ion transport with high selectivity. This study was conducted to discover efficient methods for removing Cr(VI) from wastewater. A functionalized calix[4]arene carrier 1 in a PIM system was used to transport Cr(VI) from an acidic aqueous donor phase solution to an acceptor phase that contained an acetic acid/ammonium acetate solution at pH 6. The prepared PIM was characterized with Fourier Transform Infrared (FT-IR) spectroscopy and the Atomic Force Microscopy (AFM) techniques as well as with contact angle measurements. The efficiency of Cr(VI) transport through the PIM was investigated by studying the effects of carrier concentration on the membrane phase as well as by measuring the amount of plasticizer in the membrane, the pH in the acceptor phase and the membrane's stability and thickness. The kinetic parameters were calculated as rate constant (k), permeability coefficient (P), flux (J) and diffusion coefficient (Do). The transport efficiency of Cr(VI) was observed to be 98.61% after 10 h under optimized conditions. The experimental results show that Cr(VI) can transport from the donor phase to the acceptor phase with high efficiency through the PIM. The results also suggest that the transport efficiency of the PIM was reproducible and that a PIM is effective for long-term separation processes. 相似文献
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PEI Liang YAO Bing-hua WANG Li-ming MA Zhan-ying . Faculty of Water Resources Hydraulic Power Xi’an University of Technology Xi’an P. R. China . Key Laboratory of Water Cycle Related L Surface Processes Institute of Geographic Sciences Natural Resource Research Chinese Academy of Sciences Beijing 《高等学校化学研究》2011,27(1):132-139
The transport of Tb(III) in dispersion supported liquid membrane(DSLM) with polyvinylidene fluoride membrane(PVDF) as the support and dispersion solution including HCl solution as the stripping solution and di(2-ethylhexyl) phosphoric acid(D2EHPA) dissolved in kerosene as the membrane solution, has been studied. The effects of pH value, initial concentration of Tb(III) and different ionic strength in the feed phase, volume ratio of membrane solution to stripping solution, concentration of HCl solution, conc... 相似文献
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以D-( )-二苯甲酰酒石酸(D-( )-DBTA)为流动载体,研究了克伦特罗(clenbuterol,Cle)对映体的厚体液膜法拆分,建立了手性拆分条件和动力学拆分模型。考察了D-( )-DBTA浓度、缓冲液pH值对手性拆分性能的影响,进行了动力学分析,并测定了膜-料液界面的萃取反应表观速率常数k1和膜-反萃相界面的反萃取表观速率常数k2。结果表明:在优化的实验条件下(pH为7,手性载体与Cle浓度比为1∶4),Cle外消旋体能被含有手性载体D-( )-DBTA的厚体液膜有效拆分,分离因子大于1.08;Cle单体的跨膜迁移过程可以用两个串联的准一级不可逆过程进行描述。 相似文献
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十二烷基苯磺酰胺喹啉作载体的液膜法提取水中铅的研究 总被引:6,自引:0,他引:6
研究了十二烷基苯磺酰胺喹啉萃取铅(Ⅱ)的行为。研究表明,此种萃取剂在一定的条件下,能有效萃取铅(Ⅱ),并采用斜率法探讨了对铅(Ⅱ)的萃取机理。在此基础上,研究了该萃取剂作为载体的乳状液膜对铅的提取。 相似文献
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IntroductionCalixarenesconstituteaversatileclassofmacrocycliccompoundsthatcanbeeasilyfunctionalized ,thusafford ingalargevarietyofnewmultifunctionalreceptors .1Inthepasttwodecades ,theyhaveplayedanimportantroleinsupramolecularchemistryasusefulbuildingblo… 相似文献
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A new chromogenic aza-crown-ether N-(8-hydroxyquinoline-7-methylene)-4-azadibenzo-18-crown-6-ether (HQMADCE) was synthesized through the condensation reaction of 4-azadibenzo-18-crown-6-ether, 8-hydroxy quinoline and formaldehyde. The synthesized chromogenic crown was characterized by various spectroscopic techniques and its complexation with Cr(III) was studied. The parameters like extraction constant (Kex), stability constant (β), free energy change (ΔG), enthalpy change (ΔH) and change in entropy (ΔS) were calculated. Subsequently transport of Cr(III) through a bulk liquid membrane containing HQMADCE as carrier was studied. The permeation of metal was investigated as a function of various experimental variables viz. pH, carrier concentration, metal concentration and time. Furthermore, interference by other ions was also studied. 相似文献
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用甲基丙烯酸十二酯/丙烯酸共聚物作乳状液膜稳定剂迁移锌(Ⅱ);两亲高分子;乳状液膜;迁移;锌离子 相似文献
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Summary A silica gel column impregnated with bis-(2,4,4-trimethylpentyl)dithiophosphinic acid has been studied for the uptake of Ti(IV).
Its chemical stability has been examined and its regeneration power checked. The stoichiometry of the extracted species is
proposed and the loading capacity of the column material for Ti(IV) assessed. Some important binary separations of Ti(IV)
from commonly associated metal ions have been achieved and the column has been used to recover high-purity titanium from red
mud, a secondary sector material. 相似文献
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以3类含不同基团的杯[4]芳烃衍生物作为离子载体在H2O-CHCl3-H2O液膜传输体系下分别对Pb2+进行液膜传输实验. 简要讨论了以杯[4]芳烃衍生物作为离子载体对Pb2+液膜传输的动力学机理. 重点研究了不同载体种类, 载体浓度, 搅拌速度, 传输时间等因素对Pb2+传输的影响. 实验结果表明: 以含Br原子的杯[4]芳烃衍生物和含S原子的杯[4]芳烃衍生物作为离子载体对Pb2+有明显的传输效果. 可以用本文的动力学模型来描述整个传输体系的动力学特性. 相似文献