Analytical Applications of Transport Through Bulk Liquid Membranes

Abstract

This review discusses the results of research in the use of bulk liquid membranes in separation processes and preconcentration for analytical purposes. It includes some theoretical aspects, definitions, types of liquid membranes, and transport mechanism, as well as advantages of using liquid membranes in laboratory studies. These concepts are necessary to understand fundamental principles of liquid membrane transport. Due to the multiple advantages of liquid membranes several studies present analytical applications of the transport through liquid membranes in separation or preconcentration processes of metallic cations and some organic compounds, such as phenol and phenolic derivatives, organic acids, amino acids, carbohydrates, and drugs. This review presents coupled techniques such as separation through the liquid membrane coupled with flow injection analysis.

Evaluation of Kinetic Parameters at the Transport of Indole-3-acetic Acid Through Bulk Liquid Membranes

“…Assessing in time of the reduced concentrations of indole-3-acetic acid demonstrated that its pertraction through bulk liquid membrane transport system is realized after a kinetic model of consecutive irreversible first order reactions according to the equation 1: (1) where k 1 and k 2 represent pseudo-first-order apparent membrane entrance and exit rate constants, s -1 ; According to this model kinetic the variation in time of reduced concentrations respects relationships: Through the fitting of equations 8-10 with the experimental data pseudo-first-order apparent membrane entrance and exit rate constants k 1 and k 2 are obtained. From the dependence Rm = f (t) one can determine the maximum concentration of indole-3-acetic acid from the membrane.…”

“…The use of the bulk liquid membranes has been applied in many fields of research, due to their ability to transport certain compounds of interest, such as: analytical chemistry, organic chemistry and inorganic chemistry; biomedical engineering, pharmaceutical industr y, chemical industr y, biotechnology, environmental protection, as well as in wastewater treatment. Separation, removal or recovery of organic compounds, toxic metals and products of fermentation were realized using the system of de transport through liquid membranes [1][2][3][4][5][6][7][8][9][10].…”

“…The main advantage of using liquid membranes is related to obtaining a high flux of transport compared with other types of membranes (e.g. polymer membranes, inorganic membranes or hybrid organic-inorganic membranes) due to large diffusion coefficients [1][2][3][4].…”

Effects of porous media on extraction kinetics: Is the membrane really a limiting factor?

“…Membranes and porous materials are key elements in many industrial fields [1][2][3][4][5][6], whether in catalysis [7], sensor design [8][9][10][11] or in gas [12] and liquid phase separation processes [13][14][15][16]. In the later field, membranes are especially studied in ion extraction using pertraction.…”

Liquid Membranes as a Tool for Chemical Speciation of Metals in Natural Waters: Organic and Inorganic Complexes of Nickel

“…Nevertheless, recent studies suggest that competitive ligand–stripping voltammetry methods overestimate metal complexation by DOM (Dissolved organic Matter) and therefore underestimate metal concentration in comparison with model predictions (WHAM VII) [ 16 ]. Among others separation methods, solid phase and liquid-liquid extractions have been extensively used, while recently, liquid membranes have been described as a clean, useful and powerful alternative to these classical methods [ 17 , 18 ].…”