Journal•ISSN: 0001-1541

# Aiche Journal

About: Aiche Journal is an academic journal. The journal publishes majorly in the area(s): Mass transfer & Heat transfer. It has an ISSN identifier of 0001-1541. Over the lifetime, 16247 publication(s) have been published receiving 618554 citation(s).

Topics: Mass transfer, Heat transfer, Adsorption, Turbulence, Laminar flow

##### Papers published on a yearly basis

##### Papers

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TL;DR: In this paper, a new equation based on Scott's two-liquid model and on an assumption of nonrandomness similar to that used by Wilson is derived, which gives an excellent representation of many types of liquid mixtures.

Abstract: A critical discussion is given of the use of local compositions for representation of excess Gibbs energies of liquid mixtures. A new equation is derived, based on Scott's two-liquid model and on an assumption of nonrandomness similar to that used by Wilson. For the same activity coefficients at infinite dilution, the Gibbs energy of mixing is calculated with the new equation as well as the equations of van Laar, Wilson, and Heil; these four equations give similar results for mixtures of moderate nonideality but they differ appreciably for strongly nonideal systems, especially for those with limited miscibility. The new equation contains a nonrandomness parameter α12 which makes it applicable to a large variety of mixtures. By proper selection of α12, the new equation gives an excellent representation of many types of liquid mixtures while other local composition equations appear to be limited to specific types. Consideration is given to prediction of ternary vapor-liquid and ternary liquid-liquid equilibria based on binary data alone.

5,272 citations

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TL;DR: In this paper, the relation of P to conveniently available properties of dilute solutions is generalized to permit estimation of diffusion coefficients for engineering purposes for convective transport due to volume changes on mixing is negligible and other possible modes of mass transfer are not operative.

Abstract: Equation i 1) is strictly applicable in ideal dilute solutions in which convective transport due to volume changes on mixing is negligible, and in which other possible modes of mass transfer are not operative. This paper represents an attempito generalize the relation of P to conveniently available properties of dilute solutions so as to permit estimation of diffusion coefficients for engineering purposes.

3,906 citations

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TL;DR: The UNIQUAC equation as discussed by the authors is a semi-theoretical equation for the excess Gibbs energy of a liquid mixture, which is generalized through introduction of the local area fraction as the primary concentration variable.

Abstract: To obtain a semi-theoretical equation for the excess Gibbs energy of a liquid mixture, Guggenheim's quasi-chemical analysis is generalized through introduction of the local area fraction as the primary concentration variable. The resulting universal quasi-chemical (UNIQUAC) equation uses only two adjustable parameters per binary. Extension to multicomponent systems requires no ternary (or higher) parameters.
The UNIQUAC equation gives good representation of both vapor-liquid and liquid-liquid equilibria for binary and multicomponent mixtures containing a variety of nonelectrolyte components such as hydrocarbons, ketones, esters, amines, alcohols, nitriles, etc., and water. When well-defined simplifying assumptions are introduced into the generalized quasi-chemical treatment, the UNIQUAC equation reduces to any one of several well-known equations for the excess Gibbs energy, including the Wilson, Margules, van Laar, and NRTL equations.
The effects of molecular size and shape are introduced through structural parameters obtained from pure-component data and through use of Staverman's combinatorial entropy as a boundary condition for athermal mixtures. The UNIQUAC equation, therefore, is applicable also to polymer solutions.

3,856 citations

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TL;DR: In this paper, a simple technique is described for calculating the adsorption equilibria for components in a gaseous mixture, using only data for the pure-component adaption equilibrium at the same temperature and on the same adsorbent.

Abstract: A simple technique is described for calculating the adsorption equilibria for components in a gaseous mixture, using only data for the pure-component adsorption equilibria at the same temperature and on the same adsorbent. The proposed technique is based on the concept of an ideal adsorbed solution and, using classical surface thermodynamics, an expression analogous to Raoult's law is obtained. The essential idea of the calculation lies in the recognition that in an ideal solution the partial pressure of an adsorbed component is given by the product of its mole fraction in the adsorbed phase and the pressure which it would exert as a pure adsorbed component at the same temperature and spreading pressure as those of the mixture. Predicted isotherms give excellent agreement with experimental data for methane-ethane and ethylene-carbon dioxide on activated carbon and for carbon monoxide-oxygen and propane-propylene on silica gel. The simplicity of the calculation, which requires no data for the mixture, makes it especially useful for engineering applications.

2,717 citations

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TL;DR: In this article, a group-contribution method is presented for the prediction of activity coefficients in nonelectrolyte liquid mixtures, which combines the solution-of-functional-groups concept with a model for activity coefficients based on an extension of the quasi chemical theory of liquid mixture (UNIQUAC).

Abstract: A group-contribution method is presented for the prediction of activity coefficients in nonelectrolyte liquid mixtures. The method combines the solution-of-functional-groups concept with a model for activity coefficients based on an extension of the quasi chemical theory of liquid mixtures (UNIQUAC). The resulting UNIFAC model (UNIQUAC Functional-group Activity Coefficients) contains two adjustable parameters per pair of functional groups.
By using group-interaction parameters obtained from data reduction, activity coefficients in a large number of binary and multicomponent mixtures may be predicted, often with good accuracy. This is demonstrated for mixtures containing water, hydrocarbons, alcohols, chlorides, nitriles, ketones, amines, and other organic fluids in the temperature range 275° to 400°K.

2,607 citations