柠檬酸稀溶液的络合萃取研究

利用磷酸三丁酯（TBP）、三烷基胺（7301）为络合剂,分别采用甲苯、正辛醇、煤油作为稀释剂萃取柠檬酸稀溶液。实验结果表明,用混合型络合剂对柠檬酸稀溶液进行萃取,具有相当高的分配系数。考察了柠檬酸溶液初始浓度、有机相中络合剂浓度、温度对络合萃取相平衡分配 系数的影响,获得了萃取工艺过程较佳的操作条件;并对三烷基胺萃取柠檬酸稀溶液的机理进行了探讨,证实了三烷基胺对柠檬酸的萃取时同时存在离子缔合成盐和氢键缔合溶剂化两种历程。     

β-萘酚稀溶液的络合萃取

利用磷酸三丁酯(TBP)、三烷基胺(7301)为络合剂,分别采用苯、甲苯、正辛醇、煤油作为稀释剂对(-萘酚稀溶液进行络合萃取.实验结果表明,采用磷酸三丁酯-甲苯混合溶剂对( -萘酚稀溶液进行萃取,具有相当高的分配系数.同时考察了有机相中络合剂浓度、β -萘酚溶液初始浓度、溶液pH值以及温度对络合萃取相平衡分配系数的影响,建立了分配系数与稀释剂物理参数间的经验方程.     

三烷基胺(7301)络合萃取对氨基苯磺酸稀溶液

利用三烷基胺 (730 1 )为络合剂 ,在较宽的 pH值条件下实验测定了对氨基苯磺酸稀溶液的萃取相平衡分配系数 ;分析了络合剂浓度、稀释剂种类以及溶液 pH值对络合萃取相平衡分配系数的影响 ;讨论了络合剂萃取对氨基苯磺酸偶极离子的质子转移过程 ,提出了平衡分配系数D值的表达式 .     

β—萘酚然溶液的络合萃取

利用磷酸三丁酯（TBP），三烷基胺（7301）为络合剂，分别采用苯，甲苯，正辛醇，煤油作为稀释剂对β－萘酚稀溶液进行络合萃取。实验结果表明，采用磷酸三丁酯－甲苯混合溶剂对β－萘酚稀溶液进行萃取，具有相当高的分配系数。同时考察了有机相中络合剂浓度，β－萘酚溶液初始浓度，溶液pH值以及温度对络合萃取相平衡分配系数的影响，建立了分配系数与稀释剂物理参数间的经验方程。     

不同pH值下酚类的络合萃取

络合萃取法分离极性有机物稀溶液具有高效性和高选择性。在已有工作基础上,利用三正辛胺(TDA)、磷酸三丁酯(TBP)为络合剂,正辛醇、甲墓异丁基酮(MIBK)或煤油为稀释剂,在较宽的pH值条件下实验测定了酚类稀溶液的萃取相平衡分配系数;讨论了络合剂种类、络合剂浓度、稀释剂种类以及被萃取溶质种类对络合萃取相平衡分配系数的影响;提出了同时考虑络合萃取作用和物理萃取作用的平衡分配系数的表达式。     

三烷基氧膦络合萃取一元有机羧酸

络合萃取法对极性有机物稀溶液的分离具有高效性和高选择性。选择甲酸、乙酸、丙酸、丁酸为分离对象 ,三烷基氧膦 (TRPO)为络合剂 ,煤油为稀释剂 ,进行了系统的萃取相平衡实验 ,测定了络合剂浓度、稀释剂组成等因素对萃取平衡分配系数的影响。实验结果表明 ,溶质的亲油性对络合萃取平衡影响起主导作用 ;随TRPO浓度增大 ,萃取平衡分配系数呈增大趋势 ;随溶质初始浓度增大 ,有机相的溶质浓度向饱和萃取量接近 ;饱和萃取量随络合剂浓度的增大而增大。对相平衡分配系数进行拟合 ,精度令人满意。     

S—十六烷基异硫脲盐酸盐对一元有机酸的络合萃取研究

本文以 S-十六烷基异硫脲盐酸盐为络合剂 ,正辛醇、石油醚、二氯甲烷等为稀释剂 ,测定了络合萃取剂对乙酸、一氯乙酸、二氯乙酸和三氯乙酸稀溶液的相平衡分配系数 ,讨论了稀释剂种类和络合剂浓度对分配系数 D值的影响 ,确定形成的络合物的组成     

3-羟基丙酸稀溶液的络合萃取

以三辛胺为萃取剂,分别用正辛醇、二氯甲烷、乙酸乙酯、4-甲基-2-戊酮、正己烷、环己烷为稀释剂对3-羟基丙酸稀溶液进行络合萃取,分析了稀释剂对萃取的影响,讨论了温度、溶液p H、相比及络合剂体积分数对络合萃取相平衡分配系数的影响,利用傅立叶红外光谱仪测定了负载有机相中萃合物的结构,对三辛胺络合萃取3-羟基丙酸的机理进行了探讨.结果表明,正辛醇作稀释剂萃取效果最好,平衡分配系数高达4.46.以Na OH溶液进行反萃,3-羟基丙酸的反萃率为99.6%.     

有机胺类稀溶液的络合萃取

以P204(磷酸二(2-乙基己基)酯)为络合剂,加氢煤油为稀释剂,实验研究了不同的有机胺类稀溶液的络合萃取特性,讨论了有机胺类的pK_a值、络合剂的含量和溶液pH值等因素对络合萃取平衡的影响,提出了同时考虑络合萃取作用和物理萃取作用的萃取相平衡分配系数表达式。利用傅立叶红外谱图分析了P204络合萃取有机胺类的机理。     

磷酸三丁酯络合萃取丁酸的研究

用络合萃取法分离极性有机稀溶液 ,具有高效性和高选择性。利用磷酸三丁酯 (TBP)为络合剂 ,分别采用甲苯、异丙基甲酮、正辛醇、煤油作为稀释剂萃取丁酸稀溶液 ,系统研究了不同稀释剂对络合萃取平衡的影响 ,最终从效能、毒性、价格等综合因素考虑 ,选用正辛醇作为稀释剂 ;分析了络合剂浓度、丁酸溶液初始浓度、溶液 pH值以及温度对络合萃取相平衡分配系数的影响 ;利用红外光谱测定了负载有机相中萃合物的结构 ;并进行了有机溶剂的再生研究     

Effect of ph on the extraction characteristics of succinic acid and the stability of colloidal liquid aphrons

Predispersed solvent extraction (PDSE) by colloidal liquid aphrons (CLAs) was used for the extraction of succinic acid from aqueous solution. The loading values for succinic acid in PDSE by CLAs increased with increasing pH values in aqueous phase. This was due to increasing of the concentration of the undissociated succinic acid. The extractability of PDSE was higher than that of conventional contacting type extraction because of the interaction between factant and acid molecule. The stability of CLAs increased with increasing of the pH values in aqueous phase and decreasing of trioctylamine (TOA) concentration in organic phase. However, the structure of CLAs was stable at all the pH range except very low pH condition. This paper is dedicated to Professor Wha Young Lee on the occasion of his retirement from Seoul National University.     

Fractionation of Carboxylic Acids Mixture Obtained by Succinic Fermentation using Reactive Extraction

Formic, acetic, and succinic acids have been selectively separated from their mixture obtained by A. succinogenes fermentation using reactive extraction with tri-n-octylamine (TOA) dissolved in three solvents with different polarities (n-heptane, butyl acetate, and dichloromethane) without and with 1-octanol addition. This technique allows recovering formic and acetic acids from the mixture, the raffinate containing only succinic acid. The extractant concentration and organic phase polarity control the selectivity of acids extraction. Thus, at pH = 1, the selectivity factor increased from 92, in the absence of 1-octanol; to 148, in the presence of this alcohol in organic phase. The corresponding optimum concentrations of TOA in the solvent were 30 and 50 g/l, respectively. The total separation of monocarboxylic acids from the mixture with succinic acid is possible by a multi-stage extraction process, adjusting the extractant concentration in each stage to that stoechiometrically needed for reactions with formic and acetic acids only. The addition of 1-octanol reduces the number of required extraction stages.     

Extraction of uranium (VI) from hydrochloric acid solutions by long-chain aliphatic amines

The partition of uranium (vi) between hydrochloric acid solutions and organic solutions of long-chain aliphatic amines has been investigated at different concentrations of hydrochloric acid, solvent and aqueous uranium, and at different temperatures. The effects of amine structure and of organic solvent and the mechanism of uranium extraction are discussed on the basis of the results obtained. From infra-red spectral measurements it is postulated that a chloro complex of uranium (vi) is formed in the extraction of uranium (vi) from hydrochloric acid solution by tri-n-dodecylamine in benzene.     

Water enhanced solubilities of succinic acid in reactive extraction using tertiary amines/alcohols systems

Tertiary amines were used as the extradants for reactive extraction in alcohol diluents. Equilibrium and hydration data for various alcohol diluents and tertiary amines were obtained. From these data, the effect of coextracted water on extractability was investigated. For the measurement of the water-enhanced solubilities of succinic acid, the sensitivity index was introduced. The amount of coextracted water into organic phase was increased with the chain length of alcohol diluents. However, the water-enhanced solubility of succinic acid was almost constant with the chain length of alcohol diluents. The sensitivity indices were proportional to the chain length of tertiary amines; thus, the water-enhanced solubilities of succinic acid were increased.     

三辛胺萃取丁二酸、苹果酸、马来酸、富马酸特性的研究

Extraction equilibrium features of succinic acid, malic acid, maleic acid and fumaric acid were investigated systematically with trioctylamine (TOA) in chloroform, 4-methyl-2-pentanone (MIBK) and 1-octanol. Fourier transform-infrared (FTIR) spectroscopic analysis of organic samples loaded with the acid shows that amine forms 1:1 complex of ion-pair association with succinic acid, malic acid and maleic acid, and 1:1, 2:1 complex of ion-pair association with fumaric acid. It is proposed that the complex forms depend on the second dissociation constant of the dibasic acid, pKa2 Results of equilibrium experiments show that diluents affect extraction behavior, and depend on the solute concentration. Protic diluents, chloroform and 1-octanol, are more effective than the others when the equilibrium solute concentration is lower than 1:1 stoichiometry of TOA to acid, otherwise the extraction ability shows that MIBK>l-octanol>chloroform for malic and maleic acids, and l-octanol>MIBK>chloroform for succinic acid.     

二次萃取蒸馏法提取废次烟叶中烟碱的研究

采用二次萃取蒸馏法,提取废次烟叶中的烟碱。废次烟叶经过浸提、萃取、硫酸反萃、二次萃取和减压蒸馏等处理以提取烟碱,用紫外分光光度法分析了烟碱含量。结果表明,较佳的工艺条件为:以4.5 g/L的NaOH溶液浸泡粉碎后的烟叶,置于60℃水浴中振荡3.5 h,过滤得浸提液;滤渣再次浸提,并将两次浸提液合并。调节浸提液pH≥13,用正己烷按照体积比1∶2萃取浸提液3次。有机相用20%硫酸溶液反萃,调节pH≥13后,用正己烷二次萃取,合并有机相,减压蒸馏,以回收有机溶剂,残液即为含量40%的烟碱产品,提取率达75%。     

磷酸三丁酯络合萃取含酚废水的应用研究

利用磷酸三丁酯、三烷基胺为络合剂,分别采用苯、甲苯、正辛醇、煤油作为稀释剂对含酚废水进行络合萃取.实验结果表明,采用磷酸三丁酯一甲苯混合溶剂对含酚废水进行萃取具有相当高的分配系数;同时探讨了络合萃取技术处理含酚废水工业化的可行性,实验结果表明具有工业化应用前景.     

Interfacial Mass Transfer in the Reactive Extraction Process of Succinic Acid from Viscous Aqueous Solutions

The reactive extraction of succinic acid with TOA dissolved in butyl acetate from viscous aqueous solutions which simulate the rheological behavior of Actinobacillus succinogenes broths underlined the strong influence of viscosity and pH on interfacial mass flow, mass transfer driving force, and mass transfer coefficient. The magnitudes of these effects are attenuated by 1-octanol addition into the solvent phase, the interfacial mass transfer rate being accelerated for 1.2-3 times, depending on the apparent viscosity and the pH-value of the aqueous solution. The influences of the extraction parameters and mechanism have been included in a mathematical model adequate for the solute mass transfer coefficient from aqueous to organic phase.     

Cloud Point Extraction of Acetic Acid from Aqueous Solution

Abstract

A new acetic acid separation method was developed through a successful combination of cloud point extraction and complex extraction technology (CPE-SE), where an acetic acid complex compound formed and was solubilized in a surfactant micelle solution, instead of an organic solvent, and then concentrated into one phase by a phase separation process of the CPE technology. Since no organic solvent diluents were used, the new process was environmentally friendly and with a lower cost; meanwhile, the high selectivity of the complex extraction based on chemical complexation and high efficiency of CPE were also inherited as advantages over conventional solvent extraction process. In consideration of the compatibility and the related CPE characteristics, tributyl phosphate and PEG/PPG-18/18 Dimethicone were selected as complexing agent and surfactant of the CPE-SE system, respectively, and the extraction system was optimized by studying the effect of the main process parameters, including surfactant and complexing agent concentration, temperatures for the stirring and incubation steps, on the recovery and the distribution coefficient. A relative high recovery of 71.4% and a distribution coefficient of 1.4 were achieved simultaneously with the optimized process in the treatment of 0.1 M acetic acid solution. Based on its competitive extractability, high efficiency, low-cost, and environment friendlyness, the CPE-SE process was expected to be a potential separation method for a dilute acetic acid solution.