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1.
abstract Gas-assisted three-liquid-phase extraction (GATE), which has the advantages of both three-liquid-phase extrac-tion and solvent sublation, is a novel separation technique for separation and con...  相似文献   

2.
Teicoplanin is one of the macrocyclic glycopeptide antibiotics, which is active against Gram-positive bacteria, and has attracted a lot of attention in the field of chiral separation recently. In this work, the partition coefficients and extraction ratio of teicoplanin in three different solvent systems were studied: conventional extraction, reactive extraction and reverse micelle extraction. With conventional solvent extraction, n-butanol demonstrated high partition coefficient for teicoplanin, but low extraction ratio because of its high solubility in water. Reactive extraction of teicoplanin showed the highest partition coefficient with almost 100% recovery in organic phase when tri-n-octylmethyl ammonium chloride (TOMAC) was used as extractant and pH value was above 5.0. A reverse micelle system, consisted of isooctane 10mmol-L-1 TOMAC 1% n-octanol, also offered high separation factor for teicoplanin. The results are beneficial for the design of teicoplanin separation and purification process.  相似文献   

3.
以异辛醇为萃取剂,磺化煤油为稀释剂,从萃取剂体积分数、卤水pH值、相比、萃取时间、饱和萃取容量、反萃液pH值、反萃时间等方面考察了异辛醇对油田卤水中硼萃取的影响.结果表明:在卤水pH值为2、异辛醇体积分数为30%、相比(O/A)为1∶1、萃取时间为10 min时,通过4级萃取,硼的萃取率为95.3%;在相比为1∶l、反萃时间为10 min时用燕馏水3级反萃负载有机相,囊的反萃率达99%;整个过程穗的总回收率为94.3%.  相似文献   

4.
Teicoplanin is one of the macrocyclic glycopeptide antibiotics, which is active against Gram-positive bacteria, and has attracted a lot of attention in the field of chiral separation recently. In this work, the partition coefficients and extraction ratio of teicoplanin in three different solvent systems were studied: conventional extraction, reactive extraction and reverse micelle extraction. With conventional solvent extraction, n-butanol demonstrated high partition coefficient for teicoplanin, but low extraction ratio because of its high solubility in water. Reactive extraction of teicoplanin showed the highest partition coefficient with almost 100% recovery in organic phase when tri-n-octylmethyl ammonium chloride (TOMAC) was used as extractant and pH value was above 5.0. A reverse micelle system, consisted of isooctane 10 mmol-L^-1 TOMAC -t-1% n-octanol, also offered high separation factor for teicoplanin. The results are beneficial for the design of teicoplanin separation and purification process.  相似文献   

5.
采用二(2-乙基己基)磷酸(P204)作萃取剂,航空煤油作稀释剂,对含有钙、镁、钠、钾等金属离子的赖氨酸水溶液进行萃取,以蒸馏水作为反萃取剂对有机相进行反萃取分离实验.结果表明,原料液初始pH值在4~5、P204与煤油体积比为3:2、有机相与水相比为2:1、反应萃取时间大于30min、搅拌转速约200rpm时,能够取得较好的萃取效果.以初始pH值≥3.5的蒸馏水为反萃取剂,蒸馏水与有机相体积比4:1,在150rpm的转速下搅拌20min能够较为完全地分离出赖氨酸,然后在其它条件相同的情况下,用初始pH<1的蒸馏水对有机相再次反萃取可分离出金属离子,从而实现萃取剂的重复利用.  相似文献   

6.
CTAB/正丁醇/异辛烷反胶团法纯化α-淀粉酶   总被引:2,自引:0,他引:2  
吴雅睿  刘建  李宇亮  林舒 《应用化工》2007,36(8):737-740,744
以CTAB/正丁醇/异辛烷构成反胶团系统,通过反胶团萃取方式纯化精制α-淀粉酶。最佳反应条件为:萃取温度40℃,水相组成为NaCl 0.03 mol/L,pH12.0,有机相∶无机相=1∶2,振荡时间10 min;反萃取最佳条件为:温度60℃,水相组成为KCl 3 mol/L,pH4.0,有机相∶无机相=2∶1,反萃取振荡时间10 min。在上述条件下,经过一个萃取与反萃取循环后,α-淀粉酶的萃取率最高可达90.78%。  相似文献   

7.
以M5640为萃取剂,在CO2协同作用下,从氨?硫酸铵溶液中萃取锌,考察了萃取剂浓度、总氨浓度、相比、温度、加入CO2等因素对锌萃取率的影响. 结果表明,M5640在氨性溶液中对锌有一定的萃取能力,溶液pH值和总氨浓度对锌的萃取率影响较大,向溶液中加入CO2可明显提高M5640对锌离子的萃取能力. 在温度25℃及M5640加入量35vol%、相比O/A=2、锌离子浓度18.02 g/L、总氨浓度3 mol/L、加入CO2的条件下,锌的单级萃取率由不加CO2时的65.1%提升至97%以上,两级错流萃取锌萃取率达99.9%. 萃取得到的有机相不含氨,表明加入CO2可避免氨的共萃.  相似文献   

8.
三烷基氧磷萃取对氨基苯酚的性能   总被引:8,自引:0,他引:8  
李德亮  秦炜  戴猷元 《化工学报》2003,54(3):339-343
以三烷基氧磷(TRPO)为反应萃取剂,研究了稀释剂种类、溶液pH值等因素对对氨基苯酚稀溶液反应萃取分配系数(D)的影响,提出了同时考虑反应萃取和物理萃取作用的分配系数的表达式.结果表明:TRPO对对氨基苯酚的萃取主要通过与其中性分子的氢键缔合和溶剂化效应实现,D值的变化与中性分子的摩尔分数有关;稀释剂的极性对对氨基苯酚的萃取影响较小;除20%TRPO/正庚烷体系外,拟合实验数据得到的表观萃取平衡常数变化较小;体系的物理萃取分配常数则随TRPO浓度的增大而增大,且符合稀释剂和TRPO的物理萃取能力的简单加和;酸性、碱性和中性的反应萃取剂都可有效地萃取对氨基苯酚,萃取能力为二(2-乙基己基)磷酸> TRPO > 三烷基胺,相应的操作pH值为2~3、4~5和6.5~7.5,应用时可根据体系的pH值范围选用相应的萃取剂,而不必调节溶液的pH值.  相似文献   

9.
[omim]BF4离子液体萃取酚类化合物的研究   总被引:4,自引:3,他引:1  
采用水浴微波法合成离子液体萃取剂[omim]BF4.研究[omim]BF4对苯酚、邻甲酚等7种酚类化合物的萃取,考察了萃取时间、温度、相比及pH值对萃取效果的影响.实验结果表明:萃取10 min就可以达到平衡;随着温度升高或[omim]BF4与含酚水溶液相比的降低,分配系数降低;酚溶液在pH< pKa时,即酚类化合物主要以分子状态存在时,萃取效率较高.与萃取剂[bmim]PF6及传统有机溶剂相比,[omim]BF4萃取酚类化合物的分配系数处在同一数量级.同时对[omim]BF4萃取酚类化合物的机理进行了探讨,离子液体中的氟与酚类化合物的羟基形成了氢键.  相似文献   

10.
以中试填料萃取塔为设备研究了复合萃取剂(正辛醇和煤油)萃取林可霉素的宏观特性及传质强化。使用斜率法确定萃合物的结构和反应平衡常数以指导改进设备和强化传质;为了提高林可霉素萃取效果,考察了溶液pH值、相比(W/O)、填料类型、分布盘的使用等因素对提取林可霉素效果的影响。结果表明:以正辛醇为萃取剂萃取林可霉素的过程中,反应平衡常数K为0.072;复合萃取剂中正辛醇最佳含量为0.8(体积分数);萃取林可霉素的最佳pH值为10~11,最佳相比(W/O)为3;规整填料和散装填料萃取效果有限,分布盘可以大大加强传质,同时加装分布盘的填料萃取塔的单位体积处理量是混合澄清槽的12.8倍,萃取剂循环量大大减少。研究结果对复合萃取剂的萃取机理和填料萃取塔提取林可霉素的实际应用具有一定指导意义。  相似文献   

11.
《分离科学与技术》2012,47(13):2007-2012
A facile approach was designed to extract gold(I) from alkaline cyanide solution via a hydrometallurgy method. The performances of gold(I) extraction with furfuryl thioalcohol were investigated. The results revealed that gold(I) extraction increased with increasing extractant concentration and phase ratio but decreased with increase of pH value and god(I) concentration. The transfer speed of gold(I) between two phases was rather fast, and the extraction equilibrium could be established within 2 min. The extraction of gold(I) reached 92.7% with 15% (V/V) extractant. Gold(I) loaded in organic phase was stripped by NaOH solution, and stripping of gold(I) reached 90.2% with 0.08 mol · L?1.  相似文献   

12.
A novel extractant mixture, di-2-ethylhexyl phosphate (DEHPA) plus HX, was proposed and tested for recovering gallium from sulfate solution. It was found that the extraction capacity of DEPHA for gallium from sulfate solution could be enhanced significantly due to the synergistic effect of acidic extractant HX. Gallium extraction is negligible below pH 0 and highly sensitive to pH of aqueous phase in the range from 0 to 1, and satisfactory extraction can be gained at pH>1. More than 96% Ga extraction was obtained using 15% DEHPA plus 2% HX. Although Fe (Ⅲ) was found to be extracted preferentially to Ga (Ⅲ), effective extraction of Ga (Ⅲ) was possible by reducing ferric to the ferrous state prior to extraction. A loaded organic phase containing 0.48g L-1 Ga could be produced from solution of 0.12g L-1 Ga at A/O ratio of 4 : 1 via three mixer-settler operation stages. Gallium was stripped quantitatively from the loaded organic phase with l,5mol L-1 of sulfuric acid.  相似文献   

13.
《分离科学与技术》2012,47(12):1867-1871
Solvent extraction studies have been carried out for the recovery of cyclohexanecarboxylic acid (CCA) from simulated waste fluid. Influences of various parameters including extractant types, pH of the solution, equilibration time, and initial concentrations of CCA, etc., were studied. A mixture of toluene and 1-octanol (90:10, v/v) was found suitable for the extraction. The results showed that solution pH had a great effect on the distribution ratio, and CCA could be efficiently extracted when the pH was lower than 3.5. The extraction was found quite rapidly. The distribution ratio decreased as the initial concentration of CCA increased. The stripping rate of CCA using sodium hydroxide as stripping agent was found to be increased with the increase of alkali concentration. After back extraction once, more than 98% stripping efficiency was achieved with 0.8 mol/L sodium hydroxide solution at aqueous to organic phase (A/O) ratio 1:1 when CCA concentration was lower than 38.3 g/L. The practical extraction process was carried out for the waste fluid (concentration of CCA 36.5 g/L) discharged in the production of caprolactam from toluene. After four extraction stages at A/O ratio 1:1, the cumulative extraction recovery reached 99.3%. The practical stripping efficiency from loaded organic phase reached 98.2% in one single stage.  相似文献   

14.
由辣椒粉浸出液萃取辣椒碱   总被引:1,自引:0,他引:1  
以市售干辣椒为原料、95%乙醇为浸出剂,实验研究了溶剂萃取法由辣椒粉浸出液中萃取纯化辣椒碱的工艺条件. 在模拟体系和实际体系中均以正己烷和乙酸丁酯为萃取剂,考察了pH值和有机相/水相体积比对辣椒碱收率的影响. 结果表明酸化萃取步骤为工艺控制步骤. 模拟体系中pH值为11、体积比为7:1时乙酸丁酯对辣椒碱的萃取收率均大于90%,表明以乙酸丁酯为萃取剂,可以提高辣椒碱的浓缩度. 实际体系萃取结果与模拟体系趋同,但约20%的辣椒碱不能被萃取. 实际体系优化的工艺条件为辣椒粉用量50 g,250 mL 95%乙醇2次浸出,辣椒碱收率为97.0%;浸出液浓缩为浸膏并溶解于NaOH溶液中,在pH值13, O/W体积比1:1时萃取,再用盐酸调节水相pH<11,O/W体积比为1:5时用乙酸丁酯萃取,辣椒碱的收率为浸出量的80%左右.  相似文献   

15.
In the present article, a new separation system was employed for the extraction of cadmium from nitric acid solutions for the first time. Phosphine oxide, tris[(dibutylamino)methyl]-(7CI,8CI),which contains nitrogen atoms and phosphorus atom in molecular, was used as extractant. The influence of the following parameters was investigated: the organic/aqueous phase ratio (O/A), pH, contact time, temperature, the concentration of extractant, cadmium (Ⅱ), sodium nitrate and sodium chloride. Results demonstrated that quantitative extraction of cadmium was feasible from 50 mg/L cadmium feed solution in a single stage at pH 3.0, 15 min and O/A phase ratio 1:5 with 20% extractant in cyclohexane diluent. The cadmium extraction isotherm under different cadmium ion concentrations was established. The loaded cadmium could be stripped by 4 mol/L ammonium chloride aqueous solutions. A contrast study was carried out, and the results indicated that phosphine oxide, tris[(dibutylamino)methyl] –(7CI,8CI), could take the place of commercial organo-phosphorous extractants in the process of cadmium(II) extractions for its effectivity, stability and low price.  相似文献   

16.
《分离科学与技术》2012,47(8):1192-1197
This paper presents research on separating Cl? from zinc-bearing waste lixivium by using trioctylamine as an extractant, 2-octanol as a solvent, and sulfonated kerosene as a diluent. The effects of trioctylamine concentration, organic/aqueous phase ratio, extracting stages, and waste lixivium pH were investigated, and the process of stripping was also discussed. The optimal conditions were achieved. The extraction efficiency, separation factor, and stripping efficiency were calculated with optimal values of 99.47%, 595, and 99.99%, respectively. Besides, the extractant regenerated after stripping was observed without the emulsifying phenomenon. The mechanism of extraction and stripping was also discussed.  相似文献   

17.
选用P507(0-(2-乙基已基)-2-乙基已基磷酸酯)和N503(N,N二-(1-甲基庚基)乙酰胺)2种有机萃取剂对酚的质量浓度为4 500 mg/L的废水进行处理.在煤油体系中,考察了油水体积比、pH值、萃取体系相比、萃取温度、萃取时间等因素对P507和N503萃取剂效果的影响.试验结果表明,在pH值为3~3.5,...  相似文献   

18.
以萃取回收甲苯法生产己内酰胺废液中的己内酰胺为目的,选择氯仿作萃取剂,进行了萃取回收己内酰胺的研究。考察了原料液的pH、萃取温度、萃取时间等因素对氯仿萃取己内酰胺过程的影响。结果表明,在酸性条件下该萃取过程分配比随pH的升高而增大,当pH=7时分配比最大;萃取过程为快速过程,20 min即可达到萃取平衡;水相中硫酸铵和1-磺酸基环己烷羧酸对萃取过程有盐析效应,使分配比增大;萃取过程受温度影响不大,焓变值ΔH=2.86 kJ/mol。实验确定了pH=7时己内酰胺在有机相与水相中的分配平衡关系,当有机相和水相体积比为1时,三级错流萃取的萃取率可达到98%以上。同时,进行了工业废水的萃取验证实验,结果表明,氯仿对废水中己内酰胺的萃取效果良好。  相似文献   

19.
采用选择性溶剂化模型和定标粒子理论计算了8种盐类萃取剂在醋酸甲酯-甲醇-水三元体系中的标准摩尔溶剂化自由能,引入盐的溶解参数进行修正,并结合萃取分离实验进行验证,结果表明,随着盐的标准摩尔溶剂化自由能绝对值的增大,有机相中酯的质量分数呈线性增大,而有机相中水的质量分数则呈线性降低。静电相互作用力是影响加盐萃取效果的主要原因,盐与水(或醇)分子之间的静电自由能绝对值越大,盐对酯的萃取效果越好。采用标准摩尔溶剂化自由能的计算值可从理论上定量选择适宜的盐类作为萃取剂。  相似文献   

20.
The utilization of liquid–liquid extraction for the separation of 2-phenylbutyric acid(2-PBA) enantiomers was proposed. Factors affecting the extract process were investigated, including organic solvents, β-cyclodextrin derivatives, cyclodextrin concentration, p H and temperature. A model was proposed to describe the separation process based on the homogeneous phase reaction mechanism. Important parameters of this model were determined experimentally. The physical distribution coefficients for molecular and ionic 2-PBA were0.129 and 7.455, respectively. The equilibrium constants of the complexation reactions were 89.36 and36.78 L·mol~(-1) for(+)-and(-)-2-PBA, respectively. The model was verified by experiments and proved to be an excellent means to optimize the separation system. Through modeling prediction and experiment, the best conditions(e.g., pH value of 3.00, extractant concentration of 0.1 mol·L~(-1), temperature of 5.0 °C) were acquired. Under this condition, the maximum enantioselectivity(2.096) was obtained.  相似文献   

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