双水相萃取技术研究现状

近年来,双水相萃取(ATPE)已经发展成由计算机控制、在常规萃取设备中、能连续操作的分离技术。介绍了传统双水相体系(ATPS)和新型ATPS的特征、分相机理、工业应用的优缺点,指出寻找低成本易回收可循环利用的ATPS组成物质和对预分离物质有更高选择性的ATPS组成物质是研发新型ATPS的方向。论述了ATPS液液平衡的热力学模型、分配系数的关联方法,指出提高选择性及分离效率是ATPE应用研究的方向,指出总结分配系数影响因素规律、修正液液平衡的热力学模型是ATPE理论研究的方向。     

有机硅氧烷改性水性聚氨酯的合成

采用有机硅氧烷单体与聚醚、二羟甲基丙酸（DMPA）和甲苯二异氰酸酯（TDI）反应制备水性聚氨酯涂料。研究结果表明采用后添加有机硅氧烷单体的合成工艺,可制备贮存稳定好的水性聚氨酯乳液;凝胶渗透色谱（GPC）分析表明有机硅氧烷改性水性聚氨酯提高了聚氨酯的相对分子质量;性能测试表明有机硅氧烷改性水性聚氨酯涂料具有明显的优点：涂膜硬度高,耐沾污性、耐水性好和耐溶剂性好。     

Potassium Phosphate Salts-Based Aqueous Two-Phase Systems Applied in the Extraction of Gallic Acid from Guava

Aqueous two-phase systems (ATPS) consisting of potassium phosphate salt + alcohol or polyethylene glycol were investigated to extract gallic acid. The partitioning process was studied using purity gallic acid (GA). The constituents either promote the partition process of GA to bottom or top phase, leading to the creation of versatile systems. The salt acts as a drive force of process because it influences the value of phase pH, and consequently the deprotonation of biomolecule and its partition. The results using GA from guava are in close agreement with the model systems, validating the experimental data and supporting their applicability in real systems.     

Separation of α-ketoglutaric acid by salting-out extraction coupled with solar-driven distillation

Alpha-ketoglutaric acid (α-KG), as an essential intermediate in biosynthesis and drug synthesis, has a broad application prospect. However, the lower product concentration and impurities in the α-KG production make the downstream separation more complex and costly. In this study, α-KG was separated from biotransformation broth by salting-out extraction (SOE) combined with solar-driven distillation. First, the aqueous two-phase system (ATPS) consisting of acetone/(NH₄)₂SO₄ was selected by comparison. The effects of acetone/(NH₄)₂SO₄ concentration, temperature, α-KG concentration, and pH on the distribution behavior of α-KG in ATPS were investigated. Under the optimized conditions, higher extraction efficiency and purity of α-KG were obtained in the actual biotransformation broth. In addition, solar evaporation was used to achieve preconcentration of the organic phase and salt recovery, significantly reducing energy consumption. The method is environmentally friendly and easy to operate, providing a new idea for separating low concentration products in biosynthesis.     

双水相电泳分离氨基酸

双水相电泳是将电泳与双水相分离方法相耦合的一种新型分离技术。双水相体系因两相均富含水且界面张力低,具有良好的生物相溶性,因而在分离蛋白质等在有机溶剂中易失活和变性的有生物活性物质具有很大的优势。本文主要考察了在间歇操作过程中,双水相电泳时间、电场强度、料液初始浓度和传质面积等因素对聚乙二醇（ＰＥＧ）－葡聚糖（ＤＥＸ）－水体系中氨基酸（苯丙氨酸和这酸）的上相浓度、萃取率、和总传质量的影响,初步探讨了     

改进的T型微通道内双水相液滴的制备

研究了改进的缩口T型微通道和毛细管嵌入阶梯式T型微通道内双水相液滴的制备,基于液滴尺寸对这两种微通道进行了比较。结果表明,其流型为喷射-弹状流和喷射-滴落流,流型的转变受到两相流率控制。而在毛细管嵌入阶梯式T型微通道内,液滴的生成范围和稳定程度明显优于缩口T型微通道。在两个微通道内液滴生成尺寸的变化规律是相似的,均随着连续相流率的增大而减小,随着分散相流率的增大而增大,但毛细管嵌入阶梯式T型微通道内生成的液滴尺寸相较于缩口T型微通道更小。建立了液滴尺寸的预测模型,对两种微通道均具有良好的预测效果。     

双水相体系萃取木瓜蛋白酶的研究

采用聚乙二醇(PEG)/(NH4)2SO4双水相体系对木瓜蛋白酶进行萃取分离,研究了PEG相对分子量、PEG质量分数、(NH4)2SO4质量分数和pH值对木瓜蛋白酶分配系数及酶活力回收率的影响.结果表明,最佳萃取条件为:PEG4000质量分数6%、(NH4)2SO4质量分数18%、pH值6.0,在此条件下,木瓜蛋白酶的...     

乙醇/硫酸铵双水相体系萃取甘草酸钾的研究

实验考察了乙醇/硫酸铵双水相萃取甘草酸钾的可能性及其影响因素,结果表明,甘草酸钾在该体系的分配系数K和收率均随乙醇、硫酸铵质量分数的增加而增大,而随着pH的增加先增加后减小。且在w(乙醇)=35 1%,w(硫酸铵)=17 7%,pH=6 0左右时,分配系数K可达13 7,收率η可达96 3%。这将为甘草酸钾的提取分离提供一种新的可能。     

双水相萃取直接从枯草芽孢杆菌发酵液中提取β-甘露聚糖酶

研究了聚乙二醇(PEG)平均相对分子质量、PEG浓度、(NH4)2SO4浓度、NaCl浓度对β-甘露聚糖酶和总蛋白分配系数、相体积比和萃取率的影响。实验表明PEG100020%(m/m)和(NH4)2SO415%(m/m),NaCl为2%(m/m)组成的双水相体系,室温下直接对含菌体的枯草芽孢杆菌发酵液抽提β-甘露聚糖酶,可纯化2.76倍,萃取率达98.79%。     

PEG-(NH4)2SO4双水相萃取法提取壳聚糖酶的研究

采用PEG-(NH4)2SO4双水相体系直接从Bacillussp.LS发酵液上清液中分离壳聚糖酶。研究了体系中PEG分子量、PEG质量分数、(NH4)2SO4质量分数、NaCl质量分数和pH值对壳聚糖酶分配系数及萃取率的影响。结果表明,室温下双水相萃取最佳条件为:PEG600 20%、(NH4)2SO420%、NaCl 0.1%、pH值6.0,在此条件下壳聚糖酶分配系数达5.91,萃取率达88.7%。     

双水相萃取技术在分离提纯生物物质中的应用

简要介绍了双水相萃取技术的基本原理,在分离提纯生物物质中的应用情况以及今后的发展方向。     

Development and Evaluation of PEG-Lithium Citrate Salt Based Aqueous Two Phase System and Its Application in Partitioning of Proteins from Fish Industry Effluent

A aqueous two phase system (ATPS) comprising of PEG (Average mol. Wt: 4000, 6000, 8000) – lithium citrate salt-water systems were studied. The basic studies like binodal curve data generation and equilibrium studies were carried out. Furthermore, the binodal model and Othmer-Tobias and Bancroft models for phase equilibria were used for reproducing the experimental binodal data and phase equilibrium composition data, respectively. Good agreement was obtained with the experimental binodal data and tie line data with the models. The effective excluded volume values were obtained from the binodal model for the present ATPS. The tie line length was determined through the phase equilibrium composition data. This system was used to partition crude proteins of the fish industry effluent. The effects of PEG and salt weight fraction in terms of tie line length and effective excluded volume on partitioning coefficient of crude protein were studied in detail. From the results it was observed that, the crude proteins present in the fish effluent were partitioned in the PEG rich phase and the maximum partition coefficient of 7.82 was obtained. The results are discussed in the context of practical potential of this citrate based ATPS in separating crude proteins from fish industry effluent.     

离子液体分离体系的研究与发展

离子液体分离技术主要用于水中微量、痕量组分的分离与富集,也可用于水中有机污染物的去除,在许多方面优于传统的分离技术。离子液体分离技术的研究主要分为两个方向:离子液体双水相萃取技术和离子液体气浮溶剂浮选技术。综述了这两种技术的装置、影响因素、机理及应用,并指出了这两种技术的复合——离子液体双水相气浮溶剂浮选技术是今后的发展方向。     

偶联剂改性水性聚氨脂木器涂料

以甲苯二异氰酸酯（TDI）、聚醚二醇（N210）、二羟甲基丙酸（DMPA）为基本原料,在无溶剂的条件下,利用硅烷偶联剂通过合成和扩链的方法改性水性聚氨酯,制得了一系列不同含量硅烷偶联剂改性的水性聚氨酯乳液.性能测定表明：以此乳液再配以其他助剂制得的水性聚氨酯建筑用木器涂料,具有优异的粘附力、耐水性和力学性能.     

双水相体系酶法合成L-苯丙氨酸的研究

以天冬氨酸转氨酶为催化剂,开展了双水相体系中苯丙酮酸转氨反应制备L-苯丙氨酸的研究。双水相体系质量组成为聚乙二醇4 000(20%)/Na2HPO4(16%)。苯丙酮酸钠盐、细胞和L-苯丙氨酸在双水相体系中的分配系数分别为8.03,31.7和0.74。当底物浓度为43.4 g/L时,该体系酶法合成L-苯丙氨酸得率为78.1%,比在水溶液体系中提高了27.4%。     

Extraction and Recovery of Rutin from Acerola Waste using Alcohol-Salt-Based Aqueous Two-Phase Systems

Extraction of rutin from acerola waste was investigated using alcohol-salt-based aqueous two-phase systems (ATPS). Initially, the partitioning was studied using model systems with pure and commercial rutin. The impact of the ATPS constituents and composition, initial amount of rutin, temperature and addition of electrolytes was evaluated. Rutin can be recovered either in the alcohol-or-salt-rich phase depending on the salt used. To validate the optimization process, rutin extraction from acerola waste was carried out further. The results obtained with the real samples are in close agreement with the model systems and validate the optimization tests and support their applicability in bioresource-related processes.     

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。