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Permeation distillation membranes

The acetone-selective, siUcone mbber membrane is best used to treat dilute acetone feed streams and concentrate most of the acetone in a small volume of permeate. The water-selective, poly(vinyl alcohol) membrane is best used to treat concentrated acetone feed streams containing only a few percent water. Most of the water is then removed and concentrated in the permeate. Both membranes are more selective than distillation, which rehes on the vapor—hquid equiUbrium to achieve a separation. [Pg.87]

Reverse Osmosis. A reverse osmosis (RO) process has been developed to remove alcohol from distilled spirits without affecting the sensory properties (14). It consists of passing barrel-strength whiskey through a permeable membrane at high pressure, causing the alcohol to permeate the membrane and concentrating the flavor components in the retentate. [Pg.87]

The classification of separation methods suitable for the four mentioned selectors is summarized in Table 3.10. Note that azeotropic distillation, membrane permeation and melt crystallization are the most expensive, but unavoidable in handling more complex mixtures. [Pg.74]

Natural Gas. The principal sulfur contaminant of natural gas is another gas -hydrogen sulfide. Because it is extremely toxic, civil authorities have long forbidden significant levels of this compound in natural-gas pipelines. Hydrogen sulfide is removed from natural gas by a variety of commercial processes including reaction with aqueous solutions of oxidants, absorption into aqueous solutions of bases, distillation, and selective permeation through membranes. The end product of these processes is elemental sulfur, which can be sold and, in some cases, is worth more than the co-produced natural gas. In 1984, about 24,000 tons (24 million kilograms) of sulfur was produced from natural-gas wells in the United States. [Pg.10]

Velterop F (2011), The potential of the HybSi ceramic membrane in process intensification , Programme booklet of the International Scientific Conference on Pervaporation, Vapor Permeation and Membrane Distillation, Torun (Poland)... [Pg.148]

A porous polypropylene membrane with a water permeability coefficient of 4.2 m/s.bar is used in membrane distillation. Calculate the pure water flux for a feed temperature of 50 C and 90°C, respectively. The temperature at the permeate (distillate) side is 20°C. Neglect temperature polarization. [Pg.410]

Minimum energy required for membrane gas permeation, distillation, extraction and other separation... [Pg.831]

In this section, we wiU illustrate the calculation of the minimum energy required for a variety of separation processes, e.g. membrane gas permeation, distillation, extraction and adsorption. [Pg.831]

Pervaporation, vapour permeation and membrane distillation Principles and applications... [Pg.921]

Membrane reactors for energy applications and basic chemical production Edited by Angelo Basile, Luisa Di Paolo, Faisal Hai and Vincenzo Piemonte 11 Pervaporation, vapour permeation and membrane distillation Principles and applications... [Pg.676]

Sudoh, M., Takuwa, K., lizuka, H., and Nagamatsuya, K. (1997). Effects of thermal and concentration boundary layers on vapor permeation in membrane distillation of aqueous lithium bromide solution. J. Membr. Sci. 131, 1. [Pg.368]

An enrichment is defined as a separation process that results in the increase in concentration of one or mote species in one product stream and the depletion of the same species in the other product stream. Neither high purity not high recovery of any components is achieved. Gas enrichment can be accompHshed with a wide variety of separation methods including, for example, physical absorption, molecular sieve adsorption, equiHbrium adsorption, cryogenic distillation, condensation, and membrane permeation. [Pg.457]

An important characteristic of pervaporation that distinguishes it from distillation is that it is a rate process, not an equilibrium process. The more permeable component may be the less-volatile component. Perv oration has its greatest iitihty in the resolution of azeotropes, as an acqiinct to distillation. Selecting a membrane permeable to the minor corTiponent is important, since the membrane area required is roughly proportional to the mass of permeate. Thus pervaporation devices for the purification of the ethanol-water azeotrope (95 percent ethanol) are always based on a hydrophihc membrane. [Pg.2053]

Peivaporation is a relatively new process that has elements in common with reverse osmosis and gas separation. In peivaporation, a liquid mixture contacts one side of a membrane, and the driving force for the process is low vapour pressure on the permeate side of the membrane generated by cooling and condensing the permeate vapour. The attraction of peivaporation is that the separation obtained is proportional to the rate of permeation of the components of the liquid mixture through the selective membrane. Therefore, peivaporation offers the possibility of separating closely boiling mixtures or azeotropes that are difficult to separate by distillation... [Pg.355]

Hyperfiltration (Reverse Osmosis) is a form of membrane distillation or desalination (desalting) operating with membrane pore sizes of perhaps 1 to 10 Angstrom units. The various individual RO component technologies have improved tremendously over the last 20 to 25 years, and resistance to fouling and permeate output rates have benefited. Nevertheless, all RO plants remain susceptible to the risk of fouling, and adequate pretreatment and operation is essential to minimize this problem. [Pg.360]

Gas separations by distillation are energy-consuming processes. The driving force for the gas permeation is only the pressure difference between two compartments separated by the membrane. The permeation is governed by two parameters—diffusion and solubility ... [Pg.272]


See other pages where Permeation distillation membranes is mentioned: [Pg.454]    [Pg.454]    [Pg.123]    [Pg.477]    [Pg.367]    [Pg.81]    [Pg.833]    [Pg.615]    [Pg.33]    [Pg.5]    [Pg.394]    [Pg.430]    [Pg.827]    [Pg.91]    [Pg.74]    [Pg.446]    [Pg.446]    [Pg.449]    [Pg.1312]    [Pg.2051]    [Pg.2053]    [Pg.2055]    [Pg.136]    [Pg.61]    [Pg.63]    [Pg.65]    [Pg.148]    [Pg.256]   
See also in sourсe #XX -- [ Pg.484 , Pg.485 ]




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