Membranes membrane emulsification

K. Kandori Apphcation of Microporous Glass Membranes Membrane Emulsification. In A.G. Gaonkar (ed), Food Processing Recent Developments Elsevier, Amsterdam (1995). 

Kandori, K., Applications of microporous glass membranes membrane emulsification, mFoodProces-sing Recent Developments, Gaonkar, A.G., Ed., Isted., Elsevier, Amsterdam, 1995, pp. 113-142. 

Preparation of W/O/W Emulsion with Porous-Glass Membrane Membrane Emulsification 261... 

SM Joscelyne, G Traegardh. Food emulsions using membrane emulsification conditions for producing small droplets. J Food Eng 39(l) 59-64, 1999. 

Membrane emulsification [14] consists of forcing the dispersed phase to permeate into the continuous phase through a membrane having a uniform pore... 

Pressure applied on the dispersed phase Figure 1.1. Schematic principle of membrane emulsification. 

Membrane emulsification allows a precise control of the droplet size and monodispersity but the scale up of this process is difficult. MicroChannel emulsification is a promising technique but the low production rates restrict its use to highly monodisperse systems intended for high-technology applications. 

R. Katoh, Y. Asano, A. Furuya, K. Sotoyama, and M. Tomita Preparation of Food Emulsions Using Membrane Emulsification System. Proceedings of the 7th International Symposium on Synthetic Membranes in Science 407, Tubingen, Germany (1994). 

S. Ban, M. Kitana, and A. Yamasaki Preparation of O/W Emulsions with Poly(Oxyethylene) Hydrogenated Castor Oil by Using Spg Membrane Emulsification. Nippon Kagaku Kogaku Kaishi 8, 737 (1994). 

Joscelyne, S.M., Tragardh, G. (2000). Membrane emulsification — a literature review. Journal of Membrane Science, 169, 107-117. 

A further improvement of the multiphase reactor concept using lipase for enantioselective transformation has been recently reported, that is, an emulsion enzyme membrane reactor. Here, the organic/water interface within the pores at the enzyme level is achieved by stable oil-in-water emulsion, prepared by membrane emulsification. In this way, each pore forms a microreactor containing immobilized... 

Recent studies in the pharmaceutical field using MBR technology are related to optical resolution of racemic mixtures or esters synthesis. The kinetic resolution of (R,S)-naproxen methyl esters to produce (S)-naproxen in emulsion enzyme membrane reactors (E-EMRs) where emulsion is produced by crossflow membrane emulsification [38, 39], and of racemic ibuprofen ester [40] were developed. The esters synthesis, like for example butyl laurate, by a covalent attachment of Candida antarctica lipase B (CALB) onto a ceramic support previously coated by polymers was recently described [41]. An enzymatic membrane reactor based on the immobilization of lipase on a ceramic support was used to perform interesterification between castor oil triglycerides and methyl oleate, reducing the viscosity of the substrate by injecting supercritical CO2 [42],... 

This Part focuses on fundamentals and applications of membrane contactors and membrane emulsification. Special attention is given to the industrial application of membrane contactors. 

In these systems, the interface between two phases is located at the high-throughput membrane porous matrix level. Physicochemical, structural and geometrical properties of porous meso- and microporous membranes are exploited to facilitate mass transfer between two contacting immiscible phases, e.g., gas-liquid, vapor-liquid, liquid-liquid, liquid-supercritical fluid, etc., without dispersing one phase in the other (except for membrane emulsification, where two phases are contacted and then dispersed drop by drop one into another under precise controlled conditions). Separation depends primarily on phase equilibrium. Membrane-based absorbers and strippers, extractors and back extractors, supported gas membrane-based processes and osmotic distillation are examples of such processes that have already been in some cases commercialized. Membrane distillation, membrane... 

For these reasons, recently much attention has been put in alternative emulsification processes, such as the membrane emulsification (ME). 

Membrane emulsification is an appropriate technology for production of single and multiple emulsions and suspension. It was proposed for the first time at the 1988 Autumn Conference ofthe Society of Chemical Engineering, Japan. Since then, the method has continued to attract attention in particular in Japan, but also in Europe [1-10]. 

In the early 1990s, Nakashima et al. [2] introduced membrane technology in emulsions preparation by a direct emulsification method, whereas, in the late 1990s, Suzuki et al. used premix membrane emulsification to obtain production rates higher than other membrane emulsification methods [11]. 

The distinguishing feature of membrane emulsification technique is that droplet size is controlled primarily by the choice of the membrane, its microchannel structure and few process parameters, which can be used to tune droplets and emulsion properties. Comparing to the conventional emulsification processes, the membrane emulsification permits a better control of droplet-size distribution to be obtained, low energy, and materials consumption, modular and easy scale-up. Nevertheless, productivity (m3/day) is much lower, and therefore the challenge in the future is the development of new membranes and modules to keep the known advantages and maximize productivity. 

Considerable progress has been achieved in understanding the technology from the experimental point of view, with the establishment of many empirical correlations. On the other hand, their theoretical interpretation by means of reliable models is not accordingly advanced. The first model devoted to membrane emulsification, based on a torque balance, was proposed in 1998 by Peng and Williams [13], that is, ten years later the first experimental work was published, and still nowadays, a theoretical study aiming at a specific description of the premix membrane emulsification process is not available. 

Figure 21.1 Schematic representation (a) of membrane emulsification, where the membrane works as a high-throughput device to form droplets with regular dimensions (b) photo of an o/w emulsion...

Figure 21.2 Schematic drawing of membrane emulsification (a) mechanisms (b) operation procedures.

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