Applications of liquid membrane technology

Commercial eind laboratory applications of liquid membrane technology are discussed including gas transport, sensor development, metal ion recovery, waste treatment, biotechnology and biomedical engineering. Immobilized liquid membranes, emulsion or liquid surfactant membranes, and membrane reactors are discussed. Economic data from the literature for liquid membrane processes are presented and compared with existing processes such as solvent extraction and cryogenic distillation of air. 

Applications of liquid membrane technology, 110-122 Aqueous liquid membranes, preparation, 141,142/... 

Zhang XJ, Liu J, Fan Q, Lian Q, Zhang X, and Lu T. Industrial application of liquid membrane separation for phenolic wastewater treatment. In Li NN, Strathmann H, eds. Separation Technology, New York United Engineering Trustees, 1988 190-203. 

The extraction capabilities of liquid membranes have been used successfully in many areas. Since 1968 efforts have been made for successfirl industrial application of hquid membrane technology. Emphasis has been on facilitated transport of LSMs. Some of the possible commercial apphcations are discussed below. 

This volume Is divided Into three sections theory, carrier chemistry, and applications. The theory section Includes chapters which thoroughly describe the theory and analysis of various liquid membrane types and configurations (107-110) The carrier chemistry section contains two articles on the use of macrocycles for cation separations (111-112). The applications section begins with a survey article which thoroughly reviews the liquid membrane applications In the literature and discusses both potential and commercial aspects of liquid membrane technology. The remaining articles discuss both gas phase (113-115) and liquid phase transport (116-117). 

The tutorial section of this chapter also discusses typical experimental techniques and a survey of theoretical approaches. The authors papers enconpass the entire breadth of the technology and are presented with the intention of furthering research and industrial applications of liquid membranes. 

However, in spite of the known advantages and applications of liquid membrane separation processes in hollow-fiber contactors, there are scarce examples of industrial application. The industrial application of a new technology requires a reliable mathematical model and parameters that serve for design, cost estimation, and optimization purposes allowing to accurate process scale-up. " The mathematical modeling of liquid membrane separation processes in HFC is divided into two steps (1) the description of the diffusive mass transport rate and (2) the development of the solute mass balances to the flowing phases. 

Adoption of liquid membrane technology in process industry is increasing. However there are several limitations to such applications of liquid membranes. The primary limitations are inadequate membrane durability and low net flux. In addition, liquid membranes are single-stage processes without cascading. 

Possible applications of MIP membranes are in the field of sensor systems and separation technology. With respect to MIP membrane-based sensors, selective ligand binding to the membrane or selective permeation through the membrane can be used for the generation of a specific signal. Practical chiral separation by MIP membranes still faces reproducibility problems in the preparation methods, as well as mass transfer limitations inside the membrane. To overcome mass transfer limitations, MIP nanoparticles embedded in liquid membranes could be an alternative approach to develop chiral membrane separation by molecular imprinting [44]. 

The present review of zeolite membrane technology covers synthesis and characterization methods as well as the theoretical aspects of transport and separation mechanisms. Special attention is focused on the performance of zeolite membranes in a variety of applications including liquid-liquid, gas/vapor and reactive... 

Water reclamation, the treatment of wastewater to meet the water quality standards of various applications economically, is becoming increasingly important in view of the increasing world population and scarcity of fresh water sources. The major technology used for water reclamation is membrane technology. This entry gives an overview of the major membrane types used for water reclamation reverse osmosis, nanofiltration, ultrafiltration, microfiltration, and liquid membranes. Applications of these membranes in municipal and industrial wastewater reclamation have been described. 

The author discusses application of ELM, SLM, and polymer inclusion membrane techniques in separation of metal ions (precious metals, Cu, Ni, Zn, Pb, Cd, Cr(VI), Pu, Am, etc.) and organic pollutants (phenols and its derivatives, carboxylic acids, antibiotics, etc.) from wastewaters using laboratory, pilot, and industrial scale modules. Effects of experimental variables upon the solute flux for the various types of liquid membranes are analyzed. The author discusses potential and commercial aspects of hquid membrane technology in wastewater treatment. 

Here, a review on supported ionic liquid membrane technology including issues such as methods of preparation and characterization, stability, transport mechanisms and applications is presented. 

J>) reported on the application of emulsion liquid membrane technology to the recovery of uranium from wet process phosphoric acid. 

Siskens CAM. Applications of ceramic membranes in liquid filtration. In Bmggraaf AT and Cot L (eds.). Fundamentals oflrwrganic Membrane Science and Technology. Amsterdam, the Netherlands Elsevier, 1996, pp. 619—639. 

San Roman M.F., Bringas E., Ibanez R., and Ortiz I., Liquid membrane technology Fundamentals and review of its applications, J. Chem. Technol. Biotechnol. 85, 2, 2010. 

The application of ultrafiltration membranes, which are currently all of a polymeric nature, is more widespread because it is possible to separate smaller molecules such as sugars from larger molecules such as proteins. The main attraction for ultrafiltering cheese milk is the increased yield that results from the incorporation of whey protein into the cheese. In a traditional process these proteins remain in the waste liquid whey. The waste stream from a membrane unit still contains lactose (milk sugar) and this can be used for alcohol production, as an animal feed or as a feed to an anaerobic digester which will produce methane. The technology is being applied to both hard and soft cheese examples includes Cheddar and Camembert. 

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