【作者】 宋彩瑜；

【导师】 郭志峰；

【作者基本信息】 河北大学 ， 分析化学， 2010， 硕士

【摘要】 液膜萃取是二十世纪六十年代发展起来的一种样品前处理技术。它通过两液相间形成的界面一液相膜,将两种组成不同但又互相混溶的溶液隔开,经选择性渗透,使物质分离提纯。液膜萃取技术是一种高效、快速、经济的新型分离技术,且操作简单。这种新型的技术已经在多个领域得到应用,如气体分离、烃类提纯、湿法冶金、环境保护、生化产物的分离和提纯。不仅可以分离有机化合物还可以分离无机化合物。如农药残留分析、药物分析、环境分析、金属离子回收。本文采用液膜萃取方法以苦参碱为分析物,考察了膜液溶剂的厚度、受体相pH值、温度、及萃取时间等影响萃取效率的因素。然后对山豆根提取液进行了前处理。结果表明,受体相酸度越高越利于分析物的接收；常温下萃取效率随时间的延长而增加,效率可达到100%；有机溶剂的厚度越薄萃取效率越高。在苦参碱的前处理过程中,使用厚体液膜与支撑液膜两种膜萃取方式,都采用三氯甲烷做膜液,厚体液膜比支撑液膜的稳定性好,但单位体积接触面积小使得萃取率比支撑液膜的小。采用双层支撑液膜装置,40℃受体相pH值为1萃取1 h,苦参碱萃取率达58%。采用双膜萃取虽然增加了苦参碱的迁移距离,但由于单位体积接触面积大在适宜的温度下仍能达到较高的萃取率。双层支撑液膜装置在生物碱分离过程中具有较好的稳定性,能够采用易挥发的有机溶剂作膜液并能维持较高的萃取效率。与传统的液一液萃取相比,膜萃取技术具有步骤快捷简单,消耗有机溶剂少等优点,避免了液一液萃取过程中由于使用大量有机溶剂造成的污染。更多还原

【Abstract】 Liquid membrane extraction is a sample pre-dealt technique which has developed in 1960s, It facilitates extraction without the mixing of two phases, thus eliminating emulsion formation and the need for high solvent usage.The attractive features of transport through membranes are their high selectivity and the simultaneous separation and preconcentration of elements, their simplicity, low operational costs, low energy consumption, and the fact that they can be used for a broad spectrum of elements by carefully selecting the carrier, it has becam widely used in medicine, biology, chemistry, biotechnology and water treatment.In this paper, liquid membrane extraction was employed for analyzing matrine.The influencing factors such as the thickness of membrane liquid solvents, the pH value of the acceptor, the extraction temperature and extraction time were investigated.And then, Vietnamese Sophora Root was pre-dealt. The result shows that the lower pH of the accepter can be in favor of reception of the analyte, that organic liquid which is thiner can achieve higher extraction yields, the extraction efficiency increased with the time of up to 100% at room tempeature.In the pre-dealt process of matrine, trichloromethane was selected as the organic membrane liquid.Bulk liquid membrane and supported liquid membrane extraction devices were employed respectively and the former has better stability,however,the extraction efficiency is smaller than supported liquid membrane extraction,because the small contact area per unit volume,With the condition of phosphate buffer solution (pH=1)as accepter, matrine of Sophora Root was pre-dealt.The extracting time last 1 hours and the amount of extracted matrine get to 58.31%.Utilizing upported liquid membrane extraction system, the transferred distance of matrine extended, however, due to the high solubility of trichloromethane which was used as membrane liquid, we can still get high extraction efficiency.In the process of separating alkaloids, supported liquid membrane extraction devices can offer better stability. So we can use volatile organic solvents as membrane liquid to maintain higher efficiency of extraction.Compared with the traditional pre-dealt methods of matrine, membrane extraction technique has many advantages such as simple and quick steps and less consumption of organic solvents, etc.It can avoid the pollution caused by using substantive organic solvents in liquid-liquid extraction process.更多还原