Binary vapor mixtures

Fujii, T., and Shinzato, K., Various Formulas and Their Accuracy Concerning Heat and Mass Transfer in the Vapor Boundary Layer in the Case of Laminar Film Condensation of Binary Vapor Mixtures, Int. J. Heat Mass Transfer, Vol. 36, No. 1, pp27-33, 1993. 

Calculate V, and for the binary vapor mixture hydrogen su fide(l)/ethane(2)... 

Evolution of reflectivity signals over time has been used to temporally resolve the constituents of a binary vapor mixture [102]. Since the studied solvents (ethanol and acetone) have identical refractive indices, changes in the optical reflectance of porous silicon exposed to these vapors were shown to depend upon the rates of diffusion and adsorption of these species into the material. Time-resolved refrac-tometry revealed that an equimolar mixture of acetone and ethanol vapors exhibited markedly different condensation within porous silicon than did the pure mixture constituents (figure 16.14). This method is comparable to gas chromatography in that the vapor mixture interacts with the matrix in a manner dependent upon the physical properties of its components, but the porous silicon device... 

The Stefan tube, depicted schematically in Figure 2.4, is a simple device sometimes used for measuring diffusion coefficients in binary vapor mixtures. In the bottom of the tube is a pool of quiescent liquid. The vapor that evaporates from this pool diffuses to the top of the tube. A stream of gas across the top of the tube keeps the mole fraction of diffusing vapor there to essentially nothing. The mole fraction of the vapor at the vapor-liquid interface is its equilibrium value. 

So fur we have only considered the behavior of apparently pure" acetic acid vapor. Dimerization aleo occurs in vapor mixtures containing carboxylic acide. The effect on component fugacity coefficients is easily illustrated for binary vapor mixtures containing acetic acid aed en inert substneee I. For Ibis example, the true mixture contains three species monomer, dimer, and inert. A development similar to that just preseined produces a similar expression for the dimensionless extent of reaction ... 

Nonequilibrium, or film, methods provide physically realistic formulations of the problem that yield more accurate local coefficients at the expense of complexity. Colburn and Hougen [77] developed a trial-and-error solution procedure for condensation of a single vapor mixed with a noncondensable gas. Colburn and Drew [203] extended the method to include condensation of binary vapor mixtures (with no noncondensables). Price and Bell [204] showed how to use the Colburn and Drew [203] method in computer-assisted design. 

The Stefan tube, depicted schematically in Figure 1.8, is a simple device sometimes used for measuring diffusion coefficients in binary vapor mixtures. In the bottom of the tube is a pool of quiescent liquid. The vapor that evaporates from this pool diffuses to the top of the tube. A stream of gas across the top of the tube keeps the mole fraction of the diffusing vapors there to essentially zero. The compositon of the vapor at the vapor-liquid interface is its equilibrium value. Carty and Schrodt (1975) evaporated a binary liquid mixture of acetone (1) and methanol (2) in a Stefan tube. Air (3) was used as the carrier gas. In one of their experiments the composition of the vapor at the liquid interface was yx - 0.319, y2 - 0.528, and y3 = 0.153. The pressure and temperature in the gas phase were 99.4 kPa and 328.5 K, respectively. The length of the diffusion path was 0.24 m. The MS diffusion coefficients of the three binary pairs are ... 

Different batch adsorption processes were modeled using a multilayer fccdforwaKl neural network to predict water sorption [28] or adsorption of binary vapor mixtures [29]. Breakthrough parameters of an ion-exchange column [30] or a granular activated carbon fixed bed [31] were also predicted using the same kind of perceptions. 

Eiden and Schlunder [73] proposed a model for predicting the adsorption equilibria of a binary vapor mixture based on pure component parameters. The model... 

T.J. Nielsen and J.R. Giacin, The sorption of Umonene/ethyl acetate binary vapor mixtures by a biaxiaUy oriented polypropylene fihn, Packag. Technol. Sci., 7 (1994) 247-258. 

Vahdat N. Theoretical study of the performance of activated carbon in the presence of binary vapor mixtures. Carbon 1997 35(10-11) 1545-1557. 

A system of type (3) will now he discussed. Consider a tall column (Figure 8.1.3(a)), in which a binary volatile liquid mixture containing a more volatile species 1 and less volatile species 2 is flowing down the column, and a binary vapor mixture of the same species moves up the column. Details of the actual flow arrangements and column internals will be considered later. At the top of the column, the... 

Determine the expression for the fugacity coefficient of species 1 in a binary vapor mixture of 1 and 2 using the modified form of the cubic equation of state that has been recommended by Martin, as follows ... 

A binary vapor mixture contains 48% ethanol a) in water (b) at 70°C. Determine the pressure at which this vapor develops the first drop of liquid. What is the fiquid composition The excess Gibbs energy can be described by the three-suffix Margules equation with parameters ... 

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