Hollow fiber membrane solvent

King S, Meyer JS, and Andrews ARJ. Screening method for polycychc aromatic hydrocarbons in soil using hollow fiber membrane solvent microextraction. J. Chromatogr. A 2002 982 201-208. 

The mode of extraction for PAHs is highly dependent on the matrix. For solid-based matrices such as food samples, sediments, soil, marine organisms, etc. extraction methods such as Soxhlet extraction with nonpolar solvent [35 6], hollow fiber membrane solvent microextraction (HFMSME) [10], pressimzed hquid extraction (PLE) [37,38], sonication extraction [3], microwave-assisted extraction (MAE) [3], supercritical fluid extraction, (SEE) [39], accelerated solvent extraction (ASE) [40], cold extraction [41], soxtec extraction [42], microwave-assisted alkaline saponification (MAAS) [43], dynamic microwave-assisted extraction (DMAE) [44], add-induced cloud point extraction (ACPE) [45], methanolic saponification extraction (MSE) [7], etc. are employed. Of all these, Soxhlet extraction is the most common for solid samples and has achieved excellent extraction with high-level recovery but its setback is the high consmnption of solvent and time associated with it. 

Figure 8.1.35. Schematic of various large-scale liquid-liquid extraction devices, (a) Packed tower for solvent extraction (b) sieve-plate extraction column (c) an early Scheibel column extraction design (d) Karr column, in which the plates have reciprocating motions (e) centrifugal extractor (f) porous hollow fiber membrane solvent extraction device (see Figure 8.1.13(a) for a detailed design).

Pabby, A. K. Melgosa, A. Haddad, R. Sastre, A. M. Hollow fiber membrane-based non-dispersive extraction of silver(I) from alkaline cyanide media using LIX 79. International Solvent Extraction Conference, Cape Town, South Africa, Mar. 17-21, 2002, 699-705. 

Enzyme membrane reactor for production of diltiazem intermediate. A solution of the racemic ester in organic solvent enters the port at the bottom of the reactor and flows past the strands of microporous, hollow-fiber membrane that contain an enzyme. The enzyme catalyzes hydrolysis of one enantiomer of the ester that undergoes decarboxylation to 4-methoxyphenylacetaldehyde (which in turn forms a water-soluble bisulfite complex that remains in the aqueous phase). The other enantiomer of the ester remains in the aqueous stream that leaves the reactor via the port at the top. Courtesy of Sepracor, Inc. 

Pertraction A process for removing organic pollutants from industrial wastewater. The water is contacted with an organic solvent via a hollow-fiber membrane. Developed in 1994 by TNO Institute for Environmental and Energy Technology, in collaboration with Tauw Environmental Consultancy and Hoechst. 

In the past decade, several novel solvent-based microextraction techniques have been developed and applied to environmental and biological analysis. Notable approaches are single-drop microextraction,147 small volume extraction in levitated drops,148 flow injection extraction,149 150 and microporous membrane- or supported liquid membrane-based two- or three-phase microextraction.125 151-153 The two- and three-phase microextraction techniques utilizing supported liquid membranes deposited in the pores of hollow fiber membranes are the most explored for analytes of wide ranging polarities in biomatrices. This discussion will be limited to these protocols. 

By maximizing the contact area between extraction solvent and surfactant-solubilized hydrophobic oil contaminant through the use of state-of-the-art hollow fiber membrane columns, we hypothesize that hydrophobic oil contaminants can be separated from surfactant solutions without macroemulsification. For this research we were interested in the partitioning of the hydrophobic oil from the hydrophobic environment of the micelle via its aqueous concentration into a more preferred extracting solvent. 

Research on separation processes demonstrated that hydrophobic oilladen surfactant was efficiently regenerated through the use of state-of-the-art hollow fiber membrane columns. Specifically, the hydrophobic oil dodecane was effectively separated from the surfactant system SDBS/IPA/NaCl (Table VI). This separation was accomplished by counterflowing the oil/surfactant solution, comprised of 10.3 ml. dodecane per 100ml. of SDBS/IPA/NaCl solution, with the extraction solvent squalane. These results demonstrate the ability to effectively regenerate and reuse these surfactant systems. 

Figure 17.3, the reactant was fed into the solvent, while the product was extracted in water. The lipase was immobilized by entrapment method on asymmetric PAN hollow-fiber membranes. The process was run for several years with modules for the production plant of 60 m2 of active membrane area. 

Pabby, A.K. and Sastre, A.M. (2006) Hollow-fiber membrane based separation technology performance and design perspectives, in Solvent Extraction and Liquid Membranes Fundamental and Application in New Materials (eds Cortina and Aguilar), Marcel Dekker, New York. 

He, T., Versteeg, L.A.M., Mulder, M.H.V. and Wessling, M. (2004) Composite hollow-fiber membranes for organic solvent-based liquid-liquid extraction. Journal of Membrane Science, 234, 1. 

In the present work, continuous extraction of lactic acid from an aqueous solution with a solvent consisting of Alamine 336 and 2-octanol in a hollow-fiber membrane extractor was studied. The lactic acid in the solvent... 

Simultaneous extraction with solvent containing Alamine 336 and stripping with NaOH in two hollow-fiber membrane extractors from an... 

Matsumoto M, Shimauchi H, Kondo K, and Nakashio F, Kinetics of copper extraction with Kelex-100 using a hollow fiber membrane extractor, Solvent Extraction and Ion Exchange 1987, 5(2), 301-323. 

Bocquet S, Torres A, Sanchez J, Rios GM, and Romero J. Modebng the mass transfer in solvent-extraction processes with hollow-fiber membranes. AIChEJ. 2005 51(4) 1067-1079. 

Bothun GD, Knutson BL, Strobel HJ, Nokes SE, Brignole EA, and Diaz S. Compressed solvents for the extraction of fermentation products within a hollow fiber membrane contactor. J. Supercrit. Fluids 2003 25(2) 119-134. 

Bothun GD, Knutson BL, Strobel HJ, and Nokes SE. Mass transfer in hollow fiber membrane contactor extraction using compressed solvents. J. Membr. Sci. 2003 227(1-2) 183-196. 

In SLM extraction, the most widely applied type of three-phase membrane extraction, the membrane consists of an organic solvent, which is held by capillary forces in the pores of a hydrophobic porous membrane supporting the membrane liquid. Such membrane support can be either flat porous PTFE or polypropylene membrane sheet or porous polypropylene hollow fibers. Typical solvents are long-chain hydrocarbons like n-undecane or kerosene and more polar compounds like dihexyl ether, dioctyl phosphate, and others. Various additives can increase the efficiency of extraction considerably. The stability of the membrane depends on the solubility and volatility of the organic liquids, and it is generally possible to obtain membrane preparations that are stable up to several weeks. 

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