Application of membrane separation

In this chapter we will provide an overview of the application of membrane separations for chiral resolutions. As we will focus on physical separations, the use of membranes in kinetic (bio)resolutions will not be discussed. This chapter is intended to provide an impression, though not exhaustive, of the status of the development of membrane processes for chiral separations. The different options will be discussed on the basis of their applicability on a large scale. 

This paper emphasizes the "point-of-source" concept of recycling or recovering specific components for re-use through the application of membrane separation technologies. 

The application of membrane-separation processes in the treatment of wastewater of the leather industry can give a reduction of the environmental impact, a simplification of deaning-up procedures of aqueous effluents, an easy re-use of sludge, a decrease of disposal costs, and a saving of chemicals, water, and energy [22],... 

The development and application of membrane separation processes is one of the most significant advances in chemical and biological process engineering in recent years. Membrane processes are advanced filtration processes which utilise the separation properties of finely porous polymeric or inorganic films [1,2]. Membrane separations are used in a wide range of industrial processes to separate biological macromolecules, colloids, ions, solvents and gases. They also have important medical uses, especially in renal dialysis. The world-wide annual sales of membranes and membrane equipment are worth in excess of 1 billion. 

Mistry, V.V., Mabouis, J.L. 1993. Application of membrane separation technology to cheese production. In Cheese Chemistry, Physics and Microbiology. Vol. 1, General Aspects (P.F. Fox, ed.), pp. 493-522, Chapman and Hall, London. 

Applications of Membrane Separation in the Brewing Industry where... 

Reverse osmosis offers the possibility of achieving more than one purification purpose in one step. It simultaneously reduces the hardness and the concentration of other salts, as well as organic molecules, bacteria or viruses. The higher the concentration of undesired ingredients in the well water, the more economic the membrane filtration becomes as compared to the ion exchange treatment. RO for water purification is one of the oldest applications of membrane separation and has been extensively discussed in literature over the years. 

G. R. Groves, Application of membrane separation processes to the treatment of indnstrial efflnents for water reuse. Desalination 47, 277-284 (1983). 

Cellulose acetate is the material for the first-generation reverse osmosis (RO) membranes. The announcement of cellulose acetate membranes for seawater desalination by Loeb and Sourirajan in 1960 triggered the applications of membrane separation processes in many industrial sectors. Cellulose acetate membranes are prepared by the dry-wet phase inversion technique. 

K. Ito and M. Kotake, Application of membrane separation technology in food industry, Kagaku Seibutsu (Chem. Life), 1978, 16, 708-716. 

As applications of membrane separation technology expand widely, various requirements arise to membrane performance. Therefore, it is important to control membrane performance and specialize it for each application. 

Ravanchi M. T., Kaghazchi T., Kargari A. 2009. Application of membrane separation processes in petrochemical industry A review. Desalination 235 199-244. 

An RO membrane acts as a barrier to flow, allowing selective passage of a particular species (solvent) while other species (solutes) are retained partially or completely. Solute separation and permeate solvent (water in most cases) flux depend on the material selection, the preparation procedures, and the structure of the membrane barrier layer [5,15]. Cellulose acetate (CA) is the material for the first generation reverse osmosis membrane. The announcement of CA membranes for sea water desalination by Loeb and Sourirajan in 1960 triggered the applications of membrane separation processes in many industrial sectors. CA membranes are prepared by the dry-wet phase inversion technique. Another polymeric material for RO is aromatic polyamide [16]. 

Briischke, H. (1995). Industrial application of membrane separation processes. Pure and Applied Chemistry, 67, 993—1002. 

The application of membrane separators and MRs as unit operations in complex processes can provide unique opportunities for capital and operatimial cost reductions. As was the case for development of membrane materials and modules at the device level, entire processes that leverage membrane technology can be designed and optimized for specific techno-economic goals, such as profit margin, environmental emissions, or utility consumption. 

Although not applied to generic applications of membrane separations, the use of ultrasound has been shown, in one case, to enhance the operation of membranes. The particular case reported by George et al. (2008) suggested that improvements of up to 62% could be achieved in pervaporation mass transfer, although the impact on gas diffusion separation efficiency was not measurable. 

Table 3.3.14 Technically important applications of membrane separation technologies. Partly adapted from Baerns et al. (2006) details of these processes are found in Drioli and Ciorno (2009), Nunes and Peinemann (1915), and Brueschke and Melin (2006).

Mortazavi, S., Application of Membrane Separation Technology to Mitigation of Mine Effluent and Acidic Drainage. 2008, Natural Resources Canada. 194. 

Recently, the application of membrane separation techniques to the separation of CO2 has been attracting attention due to the low energy consumption compared to traditional separation methods such as gas absorption and adsorption. Although many polymeric membranes have been developed for CO2 separation, the separation factor of CO2 over N2 and CH4 is lower than about 60 1). 

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