Ethanol/isopropanol/water separation

Erlang distribution, residence time, 558 Equation of state, gases, 91 density calculation, 91 Ethanol/acetic acid separation, 385 Ethanol/butanol equilibria, 375 Ethanol/isopropanol/water separation, 421... 

Absorption is widely used as a raw material and/or product recovery technique in separation and purification of gaseous streams containing high concentrations of VOC, especially water-soluble compounds such as methanol, ethanol, isopropanol, butanol, acetone, and formaldehyde. Hydrophobic VOC can be absorbed using an amphiphilic block copolymer dissolved in water. However, as an emission control... 

Very little data exist on the separation efficiency of multilayer diffusion and capillary condensation. Asaeda and Du (1986) used a thin modified alumina membrane to separate alcohol/water gaseous mixtures at high relative pressures (near 1). The azeotropic point could be bypassed for water/ethanol and water/isopropanol mixture by employing eapillary condensation as a separation mechanism at a temperature of 70°C. By deereasing the pore size to the microporous range (pore diameter < 2 nm by plugging the pores with hydroxides), the separation faetors were inereased to above 60 (Asaeda and... 

Ethanol and isopropanol separations - all applications realized within five years. Olefins, miscellaneous hydrocarbons, water-separations - one-half of applications realized within ten years and all within fifteen years... 

Upon collection, tissues are typically frozen in liquid nitrogen and then homogenized by grinding the frozen sample to a fine powder. Extraction of tissue components is most commonly performed using LLE. Polar compounds are extracted with polar solvents including methanol, ethanol, isopropanol, acetonitrile, water, or polar solvent mixtures, while nonpolar compounds are extracted with ethyl acetate or chloroform. Such an LLE yields two fractions (polar and nonpolar) that can be analyzed separately [76,95,96],... 

The pervaporation dehydration study of isopropanol-water and ethanol-water mixtures was carried out by Moon et al. [90]. The two-ply dense composite membranes were prepared using successive castings of sodium alginate and CS solutions. The membranes showed improved mechanical strength, flux, and separation factor. The three factors like polymer type contacting the feed stream, NaOH treatment, and type of cross-linking agent decide the flux and separation factor of the two-ply membrane system. 

Figure 6.16. Trajectories of heteroazeotropic distiUation (a) distillate from azeocolumn to decanter for separation toluene(l)-ethanol(2)-water(3) mixture (b) distillate from azeocolumn to decanter and a recycle stream of the entrainer from decanter to azeocolumn for separation benzene(l)-isopropanol(2)-water(3) mixture (c) distillate from azeostripping to decanter and a recycle stream of the entrainer from decanter to azeostripping for separation benzene(l)-isopropanol(2)-water(3) mixture (d) distillate from azeocolumn to decanter and a recycle stream of the entrainer from decanter to azeocolumn for separation acetic add(l)-n-butyl acetate (2)-water(3) mixture (e) bottom from azeocolumn to decanter for separation butanol(l)-acetone(2)-water(3) mixture and (f) side product from azeocolumn to decanter for separation butanol(l)-acetone(2)-water(3) mixture. Regions of two liquid phases Regi,i 1,2 are shaded.

There are many important industrial applications of azeotropic separations, which employ a variety of methods. In this book we discuss several of these chemical systems and demonstrate the application of alternative methods of separation. The methods presented include pressure-swing distillation, azeotropic distillation with a light entrainer, extractive distillation with a heavy entrainer (solvent), and pervaporation. The chemical systems used in the numerical case studies included ethanol-water tetrahydrofuran (THF)-water, isopropanol-water, acetone-methanol, isopentane-methanol, n-butanol-water, acetone-chloroform, and acetic acid-water. Economic and dynamic comparisons between alternative methods are presented for some of the chemical systems, for example azeotropic distillation versus extractive distillation for the isopropanol-water system. 

Racemic dinitropyridyl, dinitrophenyl, and dinitrobenzoyl amino acids were resolved on C-18W/UV TLC and HPTLC plates (Macherey-Nagel) developed with 2% aqueous isopropanol containing 2-5% BSA. Development times were 1-2 h, and visualization was under 254 nm UV hght. Ri differences ranged from 0.06 to 0.49 [34]. The same plates with mobile phases composed of isopropanol -E BSA-E sodium tetraborate, acetic acid, or sodium carbonate served to separate enantiomeric D,L-methylthiohydantoin andphenylthiohydantoin derivatives of amino acids, kynureyne, 3-(l-naphthyl)alanine, lactic acid derivatives, alanine and leucine p-nitroanilides, and 2,2,2-trifluoro-l-(9-anthryl)ethanol [35], and with mobile phases composed of water with 5-7% BSA -E 2% isopropanol to separate dansyl amino acid derivatives [36]. 

Isopropanol is a colorless liquid having a pleasant odor it is soluble in water. It is more soluble in hydrocarbon liquids than methanol or ethanol. For this reason, small amounts of isopropanol may be mixed with methanol-gasoline blends used as motor fuels to reduce phase-separation problems. ... 

The recent introduction of non-aqueous media extends the applicability of CE. Different selectivity, enhanced efficiency, reduced analysis time, lower Joule heating, and better solubility or stability of some compounds in organic solvent than in water are the main reasons for the success of non-aqueous capillary electrophoresis (NACE). Several solvent properties must be considered in selecting the appropriate separation medium (see Chapter 2) dielectric constant, viscosity, dissociation constant, polarity, autoprotolysis constant, electrical conductivity, volatility, and solvation ability. Commonly used solvents in NACE separations include acetonitrile (ACN) short-chain alcohols such as methanol (MeOH), ethanol (EtOH), isopropanol (i-PrOH) amides [formamide (FA), N-methylformamide (NMF), N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMA)] and dimethylsulfoxide (DMSO). Since NACE—UV may present a lack of sensitivity due to the strong UV absorbance of some solvents at low wavelengths (e.g., formamides), the on-line coupling of NACE... 

The three current applications of pervaporation are dehydration of solvents, water purification, and organic/organic separations as an alternative to distillation. Currently dehydration of solvents, in particular ethanol and isopropanol, is the only process installed on a large scale. However, as the technology develops, the other applications are expected to grow. Separation of organic mixtures, in particular, could become a major application. Each of these applications is described separately below. 

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