Kinetics of solvent extraction-flow injection analysis
Kinetics of solvent extraction-flow injection analysis
复制标题
溶剂萃取-流动注射分析动力学
DOI：
10.1021/ac00177a005
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发表时间：
1989
期刊：
影响因子：
--
通讯作者：
F. Cantwell
中科院分区：
文献类型：
--
作者：
C. Lucy;F. Cantwell
研究了溶剂萃取-流动注射分析中仪器参数对萃取速率的影响。在直管中，对于较短的管段，萃取率随管段长度的减小而迅速增加，而对于较长的管段，萃取率几乎不变。增加线速度导致提取率的增加小于比例增加。萃取率随管直径的变化与管段的界面面积和管段长径比相关。长段内的对流是环形的，流线平行于管壁，除了段端部附近，而短段内的对流沿整个段沿着表现出显著的径向流动分量。在冷管中，提取率比可比直管中高得多。这种增强是由于在管段内产生了切向二次流，且长管段比短管段更大。溶剂萃取是流动注射分析中最常用的分离方法（1）。溶剂萃取-流动注射分析（SE-FIA）的理论研究包括相分离的起源（2）、峰面积对流速的依赖性（3）、影响峰高的因素（4）、分离过程的效率（5）、多孔膜相分离器的操作（6）、以及由萃取盘管（7）中的膜形成和相分离器（8）的死体积引起的带增宽。直到最近，理论上的一个空白，
The effect of Instrumental parameters on the rate of extraction In solvent extraction-flow Injection analysis was studied. In straight tubes, the extraction rate Increases rapidly with de-creasing segment length for short segments and Is approximately constant for longer segments. Increasing the linear velocity results In less than a proportional Increase In the extraction rate. Changes In extraction rate with tubing diam-eter are correlated with the Interfacial area of the segment and with the segment aspect ratio. The convection within long segments Is toroidal with the flow streamlines parallel to the tube wall except near the segment ends, whereas the convection In short segments exhibits a significant radial flow component along the entire segment. In colled tubes, the extraction rates are much higher than In comparable straight tubes. This enhancement Is dueto the generation of tan-gential secondary flow within the segments and Is greater for long segments thanfor short.Solvent extraction is the most frequently used separation method in flow injection analysis (1). Research on the theory of solvent extraction-flow injection analysis (SE-FIA) has addressed the origin of phase segmentation (2), the dependence of peak area on flow rate (3), the factors influencing peak height (4), the efficiency of the separation process (5), the operation of porous-membrane phase separators (6), and the band broadening that results both fromfilm formation in the extraction coil (7) and from the dead volume of the phase separator (8). Until recently, a gap in the theory of