Membrane contactors solvent extraction

Figure 23.3 Detail view of the two-phase system in membrane-based solvent extraction (MBSE) in contactor with hydrophobic wall.

Kertesz, R. and Schlosser, S. (2005) Design and simulation of two phase hollow-fiber contactors for simultaneous membrane-based solvent extraction and stripping of organic acids and bases. Separation and Purification Technology, 41, 275. 

Sciubba, L., Di Gioia, D., Fava, F. and Gostoli, C. (2008) Membrane-based solvent extraction of vanilin in hollow-fiber contactors, accepted for publication in Desalination. 

Membrane-based solvent extraction and stripping of phenylalanine in HF contactors. Journal of Membrane Science, 257, 37. 

Kubisova, L., Sabolova, E., Schlosser, S., Martak, J. and Kertesz, R. (2002) Membrane-based solvent extraction and stripping of a heterocyclic carboxylic acid in hollow-fiber contactors. Desalination, 148, 205. 

Schlosser, ., Sabolova, E. and Martak, J. (2001) Pertraction and membrane-based solvent extraction of carboxylic adds in hollow-fiber contactors, in Solvent Extraction for the 21st Century (eds M. Valiente and M. Hidalgo), Society of Chemical Industries, London, p. 1041. 

Processes for production of ethanol and acetone-butanol-ethanol mixture from fermentation products in membrane contactor devices were presented in Refs. [88,89]. Recovery of butanol from fermentation was reported in Ref. [90]. Use of composite membrane in a membrane reactor to separate and recover valuable biotechnology products was discussed in Refs. [91,92]. A case study on using membrane contactor modules to extract small molecular weight compounds of interest to pharmaceutical industry was shown in Ref. [93]. Extraction of protein and separation of racemic protein mixtures were discussed in Refs. [94,95]. Extractions of ethanol and lactic acid by membrane solvent extraction are reported in Refs. [96,97]. A membrane-based solvent extraction and stripping process was discussed in Ref. [98] for recovery of Phenylalanine. Extraction of aroma compounds from aqueous feed solutions into sunflower oil was investigated in Ref. [99]. 

Kertesz R, Schlosser S, and Simo M, Membrane bases solvent extraction and stripping of Phenylalanine in HE contactors. Euromembrane 2004, Hamburg, Germany, September 28-October 1, 2004. 

Kubisova L, Sabolova E, Schlosser S, Martak J, and Kertesz R. Mass-transfer in membrane based solvent extraction and stripping of 5-methyl-2-pyrazinecarboxylic acid and co-transport of sulphuric acid in HE contactors. Desalination, 2004 163(1-3) 27-38. 

Membrane technology may become essential if zero-discharge mills become a requirement or legislation on water use becomes very restrictive. The type of membrane fractionation required varies according to the use that is to be made of the treated water. This issue is addressed in Chapter 35, which describes the apphcation of membrane processes in the pulp and paper industry for treatment of the effluent generated. Chapter 36 focuses on the apphcation of membrane bioreactors in wastewater treatment. Chapter 37 describes the apphcations of hollow fiber contactors in membrane-assisted solvent extraction for the recovery of metallic pollutants. The apphcations of membrane contactors in the treatment of gaseous waste streams are presented in Chapter 38. Chapter 39 deals with an important development in the strip dispersion technique for actinide recovery/metal separation. Chapter 40 focuses on electrically enhanced membrane separation and catalysis. Chapter 41 contains important case studies on the treatment of effluent in the leather industry. The case studies cover the work carried out at pilot plant level with membrane bioreactors and reverse osmosis. Development in nanofiltration and a case study on the recovery of impurity-free sodium thiocyanate in the acrylic industry are described in Chapter 42. 

Membrane-assisted solvent extraction processes have known an increasing number of applications in the last decades [1 ]. This technique not only overcomes the limitations of conventional liquid extraction, such as flooding, intimate mixing, limitations on phase flow rate variations, and requirement of density difference but also provides a large surface area of mass transfer per volume of contactor [5]. Excellent reviews of the technology and its applications were presented by Ho and Sirkar in 1992 [6], and by Gabelman and Hwang [7]. 

Coelhoso I.M., Silcivestre P., Viegas R.M.C., Crespo J.P.S.G., and Carrondo M.J.T., Membrane-based solvent extraction and stripping of lactate in hollow-fiber contactors. J. Membr. Sci. 134, 19-32, 1997. 

The mass-transfer efficiencies of various MHF contactors have been studied by many researchers. Dahuron and Cussler [AlChE 34(1), pp. 130-136 (1988)] developed a membrane mass-transfer coefficient model (k ) Yang and Cussler [AIChE /., 32(11), pp. 1910-1916 (1986)] developed a shell-side mass-transfer coefficient model (ks) for flow directed radially into the fibers and Prasad and Sirkar [AIChE /., 34(2), pp. 177-188 (1988)] developed a tube-side mass-transfer coefficient model (k,). Additional studies have been published by Prasad and Sirkar [ Membrane-Based Solvent Extraction, in Membrane Handbook, Ho and Sirkar, eds. (Chapman Hall, 1992)] by Reed, Semmens, and Cussler [ Membrane Contactors, Membrane Separations Technology Principle. and Applications, Noble and Stern, eds. (Elsevier, 1995)] by Qin and Cabral [MChE 43(8), pp. 1975-1988 (1997)] by Baudot, Floury, and Smorenburg [AIChE ]., 47(8), pp. 1780-1793 (2001)] by GonzSlez-Munoz et al. [/. Memhane Sci., 213(1-2), pp. 181-193 (2003) and J. Membrane Sci., 255(1-2), pp. 133-140 (2005)] by Saikia, Dutta, and Dass [/. Membrane Sci., 225(1-2), pp. 1-13 (2003)] by Bocquet et al. [AIChE... 

With the help of hollow fiber contactors, commercial success of membrane stripping, membrane-based solvent extraction, membrane gas adsorption, and other related processes could be possible. True manbrane separation processes (e.g., reverse osmosis [RO], ultrafiltration [UF], nanofiltration [NF]) have, in general. 

The formulation of the three phases must be such that the liquid membrane extracts the solute from one of the phases and the third phase strips it from the membrane. Thus extraction and stripping take place in the same contactor, and the stripping phase is where the solute is accumulated, instead of the organic phase as in the case of conventional solvent extraction. This allows for a middle phase of small volume that, being thin, behaves like a membrane. 

Kumar, A., Haddad, R., Alguacil, F.J. and Sastre, A.M. (2005) Comparative performance of non-dispersive solvent extraction using a single module and the integrated membrane process with two hollow-fiber contactors. Journal of Membrane Science, 248, 1. 

A historical perspective on aqueous-organic extraction using membrane contactor technology is available in Refs. [1,6,83]. The mechanism of phase interface immobilization was first explored in Ref. [84], while application of membrane solvent extraction for a commercial process was first explored in Ref. [85]. Two aspects of liquid-liquid contact in membrane contactors that are different from typical gas-liquid contact are (1) the membrane used could be hydrophobic, hydrophdic, or a composite of both and (2) the membrane mass transfer resistance is not always negligible. Ensuring that the right fluid occupies the membrane pores vis-a-vis the affinity of the solute in the two phases can minimize membrane resistance. These aspects have been discussed in detail in Refs. [6,86,87]. 

As mentioned in Section 2.9, liquid-liquid extraction has also been employed on a commercial scale in membrane contactors to remove environmentally toxic species from wastewater before incineration. Photograph of such a system is shown in Figure 2.16. Multiple banks of contactors are used in the system. The solvent used for extraction is returned to the chemical process that produces the toxic compounds. 

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. 

Schlosser S, Sabolova E, and Martak J. Pertraction and membrane based extraction of carboxylic acids in hollow fibre contactors. In Cox M, Hidalgo M, and Valiente M Eds. Solvent Extraction for the 21st Century. Proceedings of ISEC 99, Barcelona, Spain, July 1999. Publisher Society of Chemical Industry, London, UK 2001 2 1041-1046. 

As a part of our comprehensive programme on membrane technology, we evaluated nondispersive solvent extraction (NDSX) with a hydrophobic microporous hollow fiber contactor (HFC) for the separation and removal of actinides [1,10-12]. As the separation and recovery of actinides from different sources is paramount to radiotoxicity, there is a constant need for advances in the field. Among recently developed technologies, membrane extraction using microporous hollow fibers is particularly... 

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