Use of supported liquid membranes

Removal of unwanted high-molecular-weight substances by size exclusion chromatography, dialysis, ultrafiltration, precipitation, and use of supported liquid membrane. 

Thoresen, K. and R.J. Fisher (1995). Use of supported liquid membranes as biomimetics of active transport processes, Biomimetics, 3, 31-66. 

ILs, on the other hand, are uniquely suited for use as solvents for gas separations. Since they are non-volatile, they cannot evaporate to cause contamination of the gas stream. This is important when selective solvents are used in conventional absorbers, or when they are used in supported liquid membranes. For conventional absorbers, the ability to separate one gas from another depends entirely on the relative solubilities (ratio of Henry s law constants) of the gases. In addition, ILs are particularly promising for supported liquid membranes, because they have the potential to be incredibly stable. Supported liquid membranes that incorporate conventional liquids eventually deteriorate because the liquid slowly evaporates. Moreover, this finite evaporation rate limits how thin one can make the membrane. This... 

Zougagh, M., Valcarcel, M., and Rios, A., Automatic selective determination of caffeine in coffee and tea samples by using a supported liquid membrane-modified piezoelectric flow sensor with molecularly imprinted polymer. Trends Anal. Chem., 23, 399, 2004. 

Other applications of supported liquid membranes have been related to metal speciation. For example, recently a system for chromium speciation has been developed based on the selective extraction and enrichment of anionic Cr(VI) and cationic Cr(III) species in two SLM units connected in series. Aliquat 336 and DEHPA were used respectively as carriers for the two species and graphite furnace atomic absorption spectrometry used for final metal determination. With this process, it was possible to determine chromium in its different oxidation states [103]. 

Mohapatra, P.K. Lakshmi, D.S. Mohan, D. Manchanda, V.K. Selective transport of cesium using a supported liquid membrane containing di-t-butyl benzo 18 crown 6 as the carrier, J. Membr. Sci. 232 (2004) 133-139. 

Papantoni, M., Djane, N.-K., Ndung u, K., Jonsson, J.A. and Mathiasson, L. (1995) Trace enrichment of metals using a supported liquid membrane technique. Analyst, 120, 1471-1477. 

Sandahl, M., L. Mathiasson, and J.A. Jonsson. 2000. Determination of thiophanate-methyl and its metabolites at trace level in spiked natural water using the supported liquid membrane extraction and the microporous membrane liquid-liquid extraction techniques combined on-line with high-performance liquid chromatography. J. Chromatogr. A 893 123-131. 

Tsai, C.Y., Chen, Y.F., Chen, W.C., Yang, F.R., Chen, J.H. and Lin, J.C. (2005) Separation of gallium and arsenic in wafer grinding extraction solution using a supported liquid membrane that contains PC88A as a carrier. Journal of Environmental Science and Health Part A-Toxic/Hazardous Substances e[ Environmental Engineering, 40, 477. 

Lindegard B, Bjork H, Jonsson JA, Mathiasson L, and Olsson A-M. Automatic column liquid chromatographic determination of a basic drug in blood plasma using the supported liquid membrane technique for sample pretreatment. Anal. Chem. 1994 66 4490-4497. 

An important number of references have been published dealing with many applications of supported liquid membranes. Mathematical modeling of the process has been developed and it can be generalized and applied to the determination of the response of different systems containing more than one solute. After evaluation of the parameters, process optimization can be applied using common optimization procedures, as described in the text. 

Miliotis, T., Knutsson, M., Jonsson, J. A., Mathiasson, L. (1996). Ion-pair extraction of aromatic anionic surfactants using the supported liquid membrane technique. Int. J. Environ. Anal. Chem., 64, 35-45. 

Drapala, A., Jonsson, J. A., Wieczorek, P. (2005). Peptides analysis in blood plasma using on-line system of supported liquid membrane and high-performance liquid chromatography. Anal. Chim. Acta, 553, 9-14. 

Megersa, N., Jonsson, J. A. (1998). Trace enrichment and sample preparation of alkylthio-s-triazine herbicides in environmental waters using a supported liquid membrane technique in combination with high-performance liquid chromatography. Analyst, 123, 225-31. 

Miyako, E., Maruyama, T., Kubota, P., Kamiya, N., Goto, M. (2005). Optical resolution of various amino acids using a supported liquid membrane encapsulating a surfactant-protease complex. Langmuir, 21, 4674-79. 

Deblay, P., Minier, M., Renon, H. (1990). Separation of L-valine from fermentation broths using a supported liquid membrane. Biotechnol. Bioeng., 35, 123-31. 

Schafer, A., Hossain, M. M. (1996). Extraction of organic acids from kiwifruit juice using a supported liquid membrane process. Bioprocess Biosyst. Eng., 16, 25-33. 

The range of apphcations of supported liquid membranes (SLMs) in the wastewater treatment is comparable to the ELM (Section 3), with respect to the range of chemicals that have been treated using this technology. This section, therefore, has a structure that is analogical to Section 3. 

It has been demonstrated that with the appropriate choice of membrane (hydro-phobic or hydrophilic polymers) the per-evaporation procedure can be efficiently applied for the quantitative and selective recovery of organic solutes, such as naphthalene, water, ethyl hexanoate and chlorobutane, from [C4CjIm]PF, IL [110]. It was also reported that the same ILs can be used as supported liquid membranes for the selective transport of secondary amines over tertiary amines with similar boiling points, and this was attributed to the higher hydrogen bond affinity of the secondary derivative with the imidazoHum cation [111,112]. 

Almeda S, Nozal L, Arce L, Valcarcel M. Direct determination of chlorophenols present in liquid samples by using a supported liquid membrane coupled in-line with capillary electrophoresis equipment. A a/C/j/m Acta 2007 587 97-103. 

Hanioka, S. et al., COj separation facilitated by task-specific ionic liquids using a supported liquid membrane. Journal of Membrane Science, 2008. 314(1) 1-4. 

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