醇-水体系汽液相平衡的盐效应及其在精馏过程的应用

加盐精馏是一种新型分离技术。本文讨论了盐对醇-水体系汽液相平衡的影响,并在理论上进行了探讨。进而论述了加盐精馏在醇-水体系分离过程的应用,包括溶盐精馏、加盐萃取精馏和加盐反应萃取精馏等,并讨论了它们的优缺点。最后,展望了加盐精馏分离醇-水体系的发展。     

有机-有机体系盐效应及其在分离过程的应用

盐效应分离是一种新型分离技术。文章系统总结了盐对有机-有机体系气-液和液-液相平衡的影响,进而论述了盐效应在有机-有机体系分离过程的应用,包括加盐萃取精馏和加盐萃取等。最后,展望了盐效应分离有机-有机体系的未来发展。     

盐效应数学模型及盐效分离过程综述

总结了现有几种盐效应气液平衡(VLE)、液液平衡(LLE)模型,对它们的优缺点进行了比较。综述了溶盐精馏、加盐萃取精馏、加盐萃取-恒沸精馏联合过程、精馏-盐效萃取耦合过程的基本原理、操作特性及适用物系,对选择应用盐效分离方法分离具体物系起到指导作用。     

萃取精馏分离甲醇-丁酮萃取剂的选择

为了解决工业生产中甲醇-丁酮共沸体系难分离的问题,本研究采用一步法合成了N-乙基吡啶溴盐([EPy][Br])、N-丁基吡啶溴盐([BPy][Br])和N-己基吡啶溴盐([HPy][Br])3种离子液体(IL),测定了101.3 kPa下这3种离子液体对甲醇-丁酮共沸物系的溶剂选择性,并考察了溶剂比对其选择性的影响,同时将离子液体的分离性能与有机溶剂进行了比较。实验结果表明:合成的3种离子液体都可提高甲醇对丁酮的相对挥发度,它们的选择性大小顺序为[EPy][Br]> [BPy][Br]> [HPy][Br],同时,它们的选择性随溶剂比的增加而增大,与常规有机溶剂相比,离子液体作为萃取剂具有显著优势。因此,可以选用[EPy][Br]作为分离甲醇-丁酮共沸物系的萃取剂。     

小分子有机溶剂双水相在分离分析中应用研究进展

小分子有机溶剂-无机盐双水相萃取技术是一种绿色高效的新分离技术,具有传统双水相萃取技术所不具备的黏度低、传质效率高、分相速度快等优点。阐述了小分子有机溶剂-无机盐双水相技术的研究现状、基本原理、影响因素和应用进展。     

离子液体/盐双水相萃取技术的研究进展

离子液体/盐双水相萃取技术是一种新型的双水相萃取技术。它具有传统双水相萃取技术所不具备的诸多优点。本文介绍了离子液体/盐双水相体系的类型和特点,综述了离子液体/盐双水相萃取技术在生物分离、天然有机物的提取、有毒物质处理中的应用,指出了该技术目前存在的问题并提出今后发展的展望。     

加盐萃取精馏分离邻二甲苯-苯乙烯的研究

测定了不同萃取剂和盐对邻二甲苯-苯乙烯近沸程物系相对挥发度的影响,研究了盐质量浓度、萃取剂加入速率和回流比对加盐萃取精馏的影响,并建立了反映塔顶馏出液中邻二甲苯质量分数与各因素关系的回归模型。研究结果表明,环丁砜(DMSO)-水(质量分数3%)-硫氰酸钾(KCNS,0.03 g/mL)可作为加盐萃取精馏分离邻二甲苯和苯乙烯体系的最佳加盐萃取剂。     

浊点萃取技术及其在分离过程中的应用

浊点萃取(CPE)技术是一种新型的环境友好的溶质富集和分离方法,其应用领域已经自最初的样品分析扩展到大规模的分离过程如水处理和生物产品提取.与传统的溶剂萃取技术相比,该技术具有快速、高效、简便、无需大量有机溶剂等特点.本文简要介绍了浊点萃取技术机理研究的新进展和近期报道的分离过程中的应用.     

浊点萃取技术在环境样品分析中的应用

浊点萃取技术(CPE)是近年来提出的一种新型的液-液、液-固萃取分离提取技术,是将表面活性剂应用于分析化学领域的一种重要而实用的技术,具有萃取效率高、富集因子大、操作简便、安全、无需大量有机溶剂等优点。适用于环境样品中金属离子及痕量有机污染物的分析。本文主要介绍了CPE技术在环境样品分析中的应用,且探讨了该技术的发展前景。     

乙醇-水体系分离技术研究进展

乙醇是重要的化工有机原料之一，被广泛应用于医疗、化妆品、卫生用品、油脂及染料等领域，与人们生活息息相关。乙醇作为一种二次清洁能源，成为各个国家能源工业发展的热点。主要介绍了乙醇-水体系分离技术（包括吸附分离、膜分离、共沸精馏、萃取精馏、溶盐精馏及加盐萃取等）的研究现状和发展前景。     

溶碱萃取剂-丁酮-水体系汽液平衡数据测定及关联

提出了溶碱萃取精馏分离丁酮-水共沸体系的方法,采用自行设计的双循环汽液平衡釜,测定了全浓度下的溶碱萃取剂-丁酮-水三元体系常压汽液平衡数据,考察了溶碱萃取剂存在下,对丁酮-水体系汽液平衡的影响。采用LIQUAC模型与Wilson模型相结合的关联计算方法,进行了汽液平衡数据的关联,关联精度较高,在此基础上,进行了萃取精馏工艺条件的模拟。结果表明,与传统的溶盐萃取剂相比,溶碱萃取剂可以更好地提高萃取精馏法分离丁酮-水体系的效果。     

Effective extraction in packed column of ethanol from the azeotropic mixture ethanol + hexane with an ionic liquid as solvent

Ionic liquids (ILs) are playing an increasingly important role in separation science. In this account, the application of ILs in all areas of separation including extraction, gas chromatography, and supported liquid membrane processes is highlighted. 1,3-Dimethylimidazolium methyl sulfate [MMIM] [MeSO₄] is suitable for use as solvent in the petrochemical extraction process for the removal of ethanol from its mixture with hexane. The knowledge of liquid–liquid equilibria (LLE) is essential for the design of the separation technique applied. For this reason, the experimental LLE for the ternary system hexane + ethanol + [MMIM] [MeSO₄] has been determined at 298.15 K. The solvent capacity of the [MMIM] [MeSO₄] is compared with other ILs. Extraction process with this solvent is simulated using conventional software and the obtained results are shown. Experimental data are obtained in a laboratory-scale packed column extraction system for the separation of this azeotropic mixture using [MMIM] [MeSO₄]. IL could be recycled and then the separating process reduces the energy consumption greatly.     

Rapid Solvent Extraction of Indium(III) and Its Separation from Gallium(III) and Aluminum(III)

Abstract

Mesityl oxide (4-methyl-3-pentene-2-one) has been used extensively for the solvent extraction separation of several transition elements (l). In the present communication, solvent extraction behavior of indium (III) toward mesityl oxide as a function of HCl or HBr concentrations has been studied and a simple and rapid method for the solvent extraction separation of gallium, indium, and aluminum has been proposed.     

苏丹高酸值重质原油脱酸新工艺探索

采用醇、胺等复合溶剂,对高酸值原油中的环烷酸进行抽提,详细讨论了抽提温度、搅拌速度、相分离时间及反应时间等因素对脱酸的影响. 实验结果表明,该方法有效地克服了乳化现象严重的缺点,经复合溶剂抽提,一次脱酸率可达70%以上.     

加速溶剂萃取技术在多环芳烃提取及检测中的应用

多环芳烃的辛醇-水分配系数较高,易被颗粒物吸附,因此检测固体中多环芳烃含量时要对样品进行萃取。加速溶剂萃取是一种全新的液-固萃取技术,具有萃取速度快、萃取剂用量少、样品回收率高等优点,对检测多环芳烃具有重要的应用价值。近几年,加速溶剂萃取技术被应用于提取土壤、水环境沉积物、空气颗粒物、纺织品等物质中的多环芳烃,不同固体样品的萃取温度、压力和萃取剂等萃取条件得到了研究探讨。     

High-performance liquid chromatography analysis of peanut phospholipids. I. Injection system for simultaneous concentration and separation of phospholipids

This paper discusses the details of a high-performance liquid chromatography method for the simultaneous concentration and separation of phospholipids or other trace compounds by direct oil injection using two different solvent systems. The system equilibrates and concentrates phospholipids on a silica column using hexane. At the same time, an analytical column is equilibrating and separating phospholipids using two binary solvent mixtures. This system eliminates a preconcentration step previously accomplished by solid-phase extraction, open-column chromatography, and other previously used methodology. Other advantages include: a 40% reduction in analysis time, elimination of a second transfer of labile compounds, decreased solvent use, and a simpler array of solvents to separate phospholipids. The method described has broader applications, such as trace organic compounds in water supplies, and trace metals with appropriate modifications for the particular analysis.     

乙醇提取油茶饼残油的研究

探讨了乙醇为溶剂热回流提取油茶饼中残油的方法。通过单因素实验及正交实验考察了乙醇体积分数、液料比、浸提温度、浸提时间及提取次数对油茶饼中残油收率的影响,确定了优化的提取条件为：乙醇体积分数95%、液料比10∶1（mL∶g）、浸提温度92℃、浸提时间3h、提取次数2次。在此优化条件下,油茶饼中平均残油收率达到残油含量的96.04%。研究结果表明,乙醇具有替代6号溶剂油提取油茶饼中残油的前景。     

预分散溶剂萃取分离苯酚溶液的研究

Predispersed solvent extraction (PDSE) is a new method for separating solutes from aqueous solution by solvent extraction and one which has shown promise for extraction from extremely dilute solution very efficient and very quick. The use of colloidal liquid aphrons in predispersed solvent extraction may ameliorate the problems such as emulsion formation, reduction of interracial mass transfer and low interfacial mass transfer areas in solvent extraction process. In present paper, colloidal liquid aphrons are successfully generated using kerosene as a solvent,tributyl phosphate(TBP) as an extractant, sodium dodecyl benzene sulphate(SDBS) as surfactant in aqueous phase and Tween-80 in oil phase. Extraction of phenol from dilute solution was studied by using colloidal liquid aphrons and colloidal gas aphrons in a semi-batch extraction column. It has been found that the PDSE process is more suitable for extraction of dilute solutions. It has also been discovered that the PDSE process has a great advantage over traditional single-stage extraction process.     

An Advanced TALSPEAK Concept for Separating Minor Actinides. Part 1. Process Optimization and Flowsheet Development

A solvent extraction system was developed for separating trivalent actinides from lanthanides. This “Advanced TALSPEAK” system uses 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (HEH[EHP]) to extract the lanthanides into an n-dodecane-based solvent; the actinides are retained in a citrate-buffered aqueous phase by complexation to a polyaminocarboxylate ligand. Several aqueous-phase ligands were investigated, and N-(2-hydroxyethyl)ethylenediamine-N,N’,N’-triacetic acid (HEDTA) was chosen for further study. Batch distribution measurements indicate that the separation of americium (Am) from the light lanthanides increases as the pH increases. However, previous investigations indicated that the extraction rates for the heavier lanthanides decrease with increasing pH. Therefore, a balance between these competing effects is required. An aqueous phase at pH 2.6 was chosen for further process development, because this offered optimal separation. Centrifugal-contactor single-stage efficiencies were measured to characterize the system’s performance under flow conditions, and an Advanced TALSPEAK flowsheet was designed.     

Effect of HEH[EHP] impurities on the ALSEP solvent extraction process

In solvent extraction processes, organic phase impurities can negatively impact separation factors, hydrolytic performance, and overall system robustness. The resulting inconsistent performance can affect the process-level viability of a separation concept, and thus knowledge of the impurities present, their effects on the process, and how to remove them are vital. Deleterious impurities may be introduced into a system from reagent synthesis, or result from degradation via radiolysis and hydrolysis during use. In this work, the acidic extractant, 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (HEH[EHP])—proposed for application in extractive processes aimed at separating trivalent minor actinides from lanthanides and other fission products—is characterized with respect to its common impurities and their impact on Am(III) stripping in the Actinide Lanthanide SEParation (ALSEP) system. To control impurities in HEH[EHP], existing purification technologies commonly applied for the acidic organophosphorus reagent were assessed and a new chromatographic purification method specific to HEH[EHP] is presented.