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。     

活性黑KN-B合成及膜处理工艺

本文对活性黑KN-B合成及膜处理工艺进行了探讨,探索了提高藏青含量的合成方法。通过高效液相色谱分析,得出最佳合成工艺条件。由于反应产物中含有大量的无机盐,染料的纯度低,因此对反应产物进行膜处理,分离反应产物中的无机盐,从而提高活性黑KN—B的纯度。     

溶剂萃取法从褐藻浸提液中分离提取褐藻糖胶

用溶剂萃取法分离提取了实际海藻浸提液中的褐藻糖胶. 考察了接触时间、溶剂加入量及萃取剂浓度等对萃取的影响，并与从多糖配制液中的萃取情况进行比较. 考察了无机盐水溶液反萃褐藻糖胶的性能及在溶剂中加入TOA(三正辛胺)对萃取和反萃的影响，结果表明，季铵盐从实际鼠尾藻浸提液中萃取褐藻糖胶受溶剂加入量的影响很大，溶剂加入量越大，萃取率越低；而萃取时间对萃取的影响不大. 海带浸提液的萃取优于鼠尾藻浸提液，而超声破碎法有利于萃取. TOA的加入既有利于褐藻糖胶的萃取也有利于无机盐水溶液反萃褐藻糖胶. 采用溶剂萃取法制备的固体褐藻糖胶的纯度优于乙醇分步沉淀法制备的固体褐藻糖胶的纯度.     

环丁砜纯度对粗苯加氢油萃取精馏系统的影响及技术优化

对粗苯加氢油萃取精馏操作过程的关键影响因素环丁砜溶剂质量进行了分析研究,阐述了溶剂纯度对萃取精馏过程分离效率的影响,确定了一定的溶剂纯度条件下最佳粗苯加氢油萃取精馏操作控制参数,实施了现有塔器高效塔内件技术改造,在稳定生产的基础上,大大提高了系统的加工能力,对萃取精馏装置的技术升级和萃取精馏过程的操作调整具有指导意义。     

一种新型的化工分离方法—萃取结晶法

萑取结晶法是用于分离沸点、挥发性等物性相近的有机物的同分异构体的有效方法同时又是生产无机盐过程中极其节能的方法。本文着重介绍了有关萃取结晶法的概念，及共理论发展，并介绍了萃取结晶法在无机盐生产和有机物混合物分离方面的应用，基于萃取结晶法的发展，预计其将在化工分离领域起到一定作用，并为基础理论发展提供依据。     

丙酮一步法生产MIBK装置的副产物精馏分离研究

针对丙酮一步法生产MIBK装置的副产物（丙酮、异丙醇、水、MIBK混合物）,采用间歇精馏分离得到纯度〉98％的丙酮、纯度〉99％的异丙醇和水恒沸物、纯度〉90％的MIBK。对分离得到的纯度〉99％的异丙醇和水恒沸物用乙二醇作为萃取剂进行萃取精馏分离得到纯度99．5％异丙醇,同时减压精馏回收乙二醇。     

萃取结晶过程研究进展

分类讨论了目前萃取结晶技术在无机盐及有机物分离领域中的应用现状、发展趋势和相应的分离原理,概括得到萃取结晶的一般原理。与传统的蒸发、结晶过程相比,萃取结晶技术具有很多优势,必将得到更大的发展。     

全氟环氧丙烷的提纯方法

研究比较了几种高效萃取溶剂萃取蒸馏分离六氟丙烯与全氟环氧丙烷的效果,提出了提纯全氟环氧丙烷的新工艺。实验结果表明溶剂萃取蒸馏提纯全氟环氧丙烷是一种经济可行、高效的途径,产品纯度达到99.6%。     

液-液萃取法从金银花中分离纯化绿原酸

为了克服传统柱色谱法的缺点,达到从金银花中分离富集绿原酸的目的,利用V(乙醇):V(乙酸乙酯)=9:91混合有机溶剂选择性萃取方法,从金银花浸膏中富集得到绿原酸萃取液,经过简单活性炭吸附除杂、减压蒸馏浓缩和重结晶得到绿原酸晶体。绿原酸的萃取率约为36.63%,纯度达98.63%。这为分离纯化绿原酸提供了一种简单高效的液-液萃取方法。     

双水相体系萃取分离金属离子研究进展

双水相体系是一种绿色环保的新型分离技术,应用领域相当广泛,是近年来的研究热点。论述了双水相体系用于萃取分离金属离子的研究现状。根据所使用萃取剂的不同分3种情况进行了论述：不添加任何萃取剂直接萃取金属离子;以无机阴离子为萃取剂,依靠金属阳离子与无机阴离子形成的阴离子配合物（螯合物）而转移到萃取相,萃取金属离子;采用有机试剂作为萃取剂,依靠金属离子与萃取剂反应形成的中性配合物（螯合物）而转移到萃取相,萃取金属离子。论述了双水相体系萃取分离金属离子的发展趋势：建立金属离子在双水相体系中分配的机理模型;双水相体系成相物质的回收及再利用;通过无机盐水化能力的差异,或者通过双水相体系的温度诱导相分离,实现无机盐的分离与常温制备;开展双水相体系萃取分离金属离子的工程研究。     

Development of a pre‐purification process for homoharringtonine

A novel pre‐purification method was developed for producing homoharringtonine from Cephalotaxus koreana, giving high purity and yield. The simple, efficient procedure involved biomass extraction, liquid–liquid extraction, and synthetic adsorbent treatment, followed by low‐pressure chromatography. The use of active clay treatment and silica gel low‐pressure chromatography in the pre‐purification process allowed for the rapid, efficient separation of homoharringtonine from interfering compounds and, compared with alternative processes, increased the yield and purity of crude homoharringtonine for subsequent high‐performance liquid chromatography (HPLC) purification. Homoharringtonine of over 52% purity could be obtained simply with high yield from biomass using this pre‐purification method, while minimizing solvent use and the scale and complexity of HPLC operations for homoharringtonine purification. Copyright © 2005 Society of Chemical Industry     

葡萄糖催化脱水制取5-羟甲基糠醛研究进展

5-羟甲基糠醛(HMF)是重要的平台化合物,是制取生物液体燃料和其他许多重要精细化工品的前驱体。以木质纤维素为原料,通过水解得到葡萄糖,葡萄糖继续脱水可以得到5-羟甲基糠醛。本文对近年来利用葡萄糖制取5-羟甲基糠醛的研究进行了综述,重点阐述了葡萄糖脱水制取5-羟甲基糠醛过程的反应机理、反应体系和催化剂,并对未来可能取得突破的研究重点进行了评述与展望。     

超临界流体与膜过程的耦合技术

介绍了超临界流体与膜过程的耦合技术的研究进展和最新研究成果。将超临界CO_2萃取与纳滤过程相耦合,可以不经历压力、温度和相变循环而使CO_2循环利用,从而降低过程能耗、减小操作费用。将纳滤过程与超临界CO_2萃取相耦合,可以对萃取收率和选择性独立调控,使它们分别达到最佳值,从而实现对萃取物在高收率条件下达到精细分离的目的。将超临界CO_2引入高粘性液体的超滤过程,会在不提高温度和无需引入化学剂的情况下,大大降低流体粘度、增大透过流率、提高过滤效率、减小过程能耗,同时也有利于环境保护、提高产品质量。     

丙酮-四氢呋喃-水混合物的清洁分离工艺的概念设计

引言 四氢呋喃（THF）既是一种性能优良的贵重有机溶剂,又是一种重要的有机合成中间体,因此在制药、涂料、皮革等领域应用广泛．当四氢呋喃用作溶剂时,由于其不被消耗,往往需要进行回收．但四氢呋喃易与水、丙酮等其他极性溶剂形成共沸物,而生产中又常需要四氢呋喃的纯度足够高,进而增加了分离提纯难度．     

Sulfonation of Triphenylphosphines and Separation of Sulfonated Triphenylphosphines by Crystallization and Solvent Extraction

Abstract

The effect of sulfonation conditions on the formation of sulfonated triphenylphosphines and their separation from the post‐reaction mixture, containing concentrated sulphuric acid, was studied. The solvent extraction was found to be a suitable technique to separate sulfonated triphenylphosphines from concentrated sulphuric acid, and the purity and yield was higher than obtained by crystallization from various solvents. Tributyl phosphate was a suitable extractant. Sodium salts of sulfonated triphenylphosphines could then be recovered as precipitates by treating the organic phase with the sodium hydroxide solution and separation by crystallization. The solvent extraction simplified the separation process. The separation process was much faster, less chemicals were required, and lower amounts of wastes were produced.     

生物油组分分离与化学品提取的研究进展

生物质在高温无氧条件下热解可以生成富含高附加值化学品和燃油成分的生物油。有效分离技术和高效提取手段的发展是生物油质量提升的关键。基于此,本文在介绍生物油性质与生物质快速热解工艺的同时,对目前国内外的生物油分离技术如蒸馏、液-液萃取、柱色谱、超临界萃取、膜分离等进行了较为详细的分析和评述。常规蒸馏和溶剂萃取等技术,工艺成熟、操作简单,但存在生物油的热敏性差、萃取剂回收难度大和污染严重等问题;分子蒸馏技术分离过程安全环保,但工艺复杂,设备成本高;超临界萃取和膜分离等技术安全环保,技术成熟,具有较大的潜力。文章还综述了目前生物油中具有高附加值的组分和单一化学品的分离提取研究进展,为生物油的有效分离和高效利用提供了理论参考,也为未来生物油分离技术的发展提供了研发方向。     

Membrane-Based Ethanol Extraction with Hollow-Fiber Module

Abstract

The high energy requirements of the traditional separation of ethanol from fermentation liquors by distillation led us to seek a new energy-efficient separation method. Several alternatives, including absorption, molecular sieves, membrane separation processes, and liquid-liquid extraction processes, have been proposed and investigated (I). One of the most investigated separation techniques during the past few years has been membrane-aided solvent extraction (2–5). This dispersion-free solvent extraction process, which uses microporous membranes, overcomes such shortcomings of conventional liquid extraction as flooding and loadings. On the other hand, a technique with microporous hollow fibers may provide high mass transfer per unit volume since hollow-fiber modules contain an enormous surface area.     

High yield production and purification of 5‐hydroxymethylfurfural

Conversion of carbohydrates to 5‐hydroxymethylfurfural (HMF) will provide a new step toward achieving renewable biomass‐based chemicals and fuels platform. Recently, the excellent yield of HMF (91.0%) in dimethyl sulfoxide (DMSO) catalyzed by sulfonated carbon was demonstrated, but the separation of HMF from the reaction mixture remains challenging because of the high boiling point of DMSO. As a solution, herein, low boiling point solvent tetrahydrofuran (THF) mixed with DMSO was used for the fructose dehydration and high yield of HMF (98.0%) was still obtained. Besides, the stability of the sulfonated carbonaceous catalyst was also confirmed. More importantly, HMF from the reaction solution was successfully separated by using simple extraction method, and high purity of HMF (ca. 96.4%) was obtained. Compared with pure DMSO solvent, the combination of low boiling point THF with DMSO not only gives higher yield of HMF, but also improves the separation efficiency and reduces environmental risk. © 2013 American Institute of Chemical Engineers AIChE J, 59: 2558–2566, 2013     

Separation of Ionic Liquid Dispersions in Centrifugal Solvent Extraction Contactors

Abstract

Separations of dispersions formed by mixing immiscible organic room‐temperature ionic liquids (IL)/hydrocarbon/and aqueous systems using a centrifugal solvent‐extraction contactor have been successfully demonstrated in proof‐of‐concept testing. This accomplishment is significant in that physical property factors that are typical of ionic liquid systems (e.g., similar densities of the bulk phases, low interfacial tensions, and high viscosities) are typically unfavorable for dispersion separation, particularly in continuous processes. Efficient separation of dispersions containing ionic liquid solvents is essential for utilization of these compounds in liquid‐liquid extraction applications to maximize both solute transfer efficiency and solvent recovery. Efficient solvent recovery is of particular concern in IL applications because of the high cost of most IL solvents.

This paper presents the results of initial experiments with three hydrophobic ionic liquids to determine how their physical properties affect phase mixing and phase disengagement in contact with an aqueous solution using a centrifugal contactor. While the results of the reported work are promising, additional work is needed to optimize existing mathematical models of contactor hydraulics to address special considerations involved in IL‐based processes and to optimize the equipment itself for IL applications.     

Separation of bio-based chemicals using pervaporation

The increasing demand of raw materials and the ever-present risk of fossil resource depletion are effective motivators for the development of new bio-based routes for the synthesis of chemicals. The use of non-renewable natural resources, such as fossil fuels, and the generation of greenhouse gases have led to severe environmental problems. However, one of the challenges of using renewable biomass resources to produce building block molecules is achieving an efficient and economically viable purification step. The complexity of the mixture involves generally high separation costs. Separation processes, such as distillation and liquid–liquid extraction, have been proposed to purify target bio-based compounds. However, the high energetic cost associated with such processes is pushing the current research towards the development of alternative solutions. In this context, membrane technology, such as pervaporation, is an interesting solution for minimizing the energy consumption of the process. This review highlights the main parameters and factors that impact the performance of pervaporation in the separation of complex bio-based chemical mixtures. Coupling effects, which are among the critical issues in pervaporation, are discussed in detail. Hybrid processes, in which both reaction and distillation are performed during the pervaporation process, are also addressed. © 2020 Society of Chemical Industry