Interfacial Transport in Reversed Micellar Extraction Processes

反胶束萃取过程中的界面传输

• 批准号: 8902349
• 负责人: Trevor Hatton
• 金额: $ 30.62万
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-08-01 至 1993-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8902349&HistoricalAwards=false
• 关键词: Interfacial; Transport; Reversed; Micellar; Extraction

This project consists of combined theoretical and experimental studies of the rates and mechanisms of interphase mass transfer in reverse micelle systems in contact with an aqueous phase. A range of solutes from low molecular weight, water soluble compounds up to globular, water soluble proteins will be studied. It is hypothesized that a different mechanism for mass transfer exists for low molecular weight compounds as opposed to the proteins. For the low molecular weight compounds it is proposed that reverse micelles form because of random thermal fluctuations of the interface which periodically result in part of the interface and the immediate aqueous phase breaking off to form a reverse micelle with some of the solute trapped in the interior. For the higher molecular weight proteins, it is hypothesized that the approach of the protein to the interface results in the spontaneous breaking off of part of the interface to form a reverse micelle, with the protein trapped in the reverse micelle. Theoretical models for these two different mechanisms have been outlined. The phenomena should exhibit very different dependence on factors such as concentration and temperature, so they should be easily distinguished if the mass transfer rate can be measured accurately. An innovative technique for measuring the mass transfer rate has been proposed for these experiments: interfacial interferometry. The refractive index of a fluid is dependent upon the concentration of any dissolved species. A beam splitter will be used to pass one part of a beam of coherent light through a layer of the liquid close to the interface between the organic and aqueous phases; when joined with the rest of the beam interference bands will be produced whose separation will be proportional to the concentration of the layer of solution through which the beam passed. By carefully controlling the position of the beam parallel to the interface with an optical bench and equipment to isolate the system from vibration, the technique should be able to accurately determine concentration as a function of distance from the interface and as a function of time. This data then can be translated very accurately into mass transfer rates. Combined with the theoretical work, this should give a very complete picture of the interphase mass transfer in the systems studied and should enable the investigator to determine the mechanisms involved. This system is one of potentially great importance to the emerging biotechnology industry. Reverse micelle extraction of proteins from aqueous solution may develop into one of the most versatile and effective bioseparation technologies. This project should add greatly to its potential for early commercial applications.

该项目包括对与水相接触的反胶束系统中相间传质的速率和机制的综合理论和实验研究。 将研究从低分子量水溶性化合物到球状水溶性蛋白质的一系列溶质。 据推测，低分子量化合物存在与蛋白质不同的传质机制。 对于低分子量化合物，提出反胶束的形成是由于界面的随机热波动，这周期性地导致部分界面和直接水相破裂，形成反胶束，其中一些溶质被截留在内部。 对于较高分子量的蛋白质，假设蛋白质接近界面导致部分界面自发断裂，形成反胶束，蛋白质被捕获在反胶束中。 已经概述了这两种不同机制的理论模型。 这些现象应该表现出对浓度和温度等因素的非常不同的依赖性，因此如果可以准确测量传质速率，那么它们应该很容易区分。 为这些实验提出了一种测量传质速率的创新技术：界面干涉测量法。 流体的折射率取决于任何溶解物质的浓度。 分束器将用于使相干光束的一部分穿过靠近有机相和水相之间界面的液体层；当与其余光束结合时，将产生干涉带，其间隔与光束穿过的溶液层的浓度成正比。 通过使用光具座和设备仔细控制平行于界面的光束位置，以将系统与振动隔离，该技术应该能够准确地确定浓度作为距界面距离的函数和时间的函数。 然后，该数据可以非常准确地转换为传质速率。 与理论工作相结合，这应该给出所研究系统中相间传质的非常完整的图景，并使研究人员能够确定所涉及的机制。 该系统对于新兴生物技术产业具有潜在的重要意义之一。 从水溶液中反胶束提取蛋白质可能会发展成为最通用和最有效的生物分离技术之一。 该项目应该会大大增加其早期商业应用的潜力。