Multicomponent equilibrium theory for ion‐exchange columns involving reactions

Hwang, Yng-Long; Helfferich, Friedrich G.; Leu, Rong-Jin

doi:10.1002/aic.690341005

Cited by 16 publications

(8 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Since the principal focus of the articles reviewed was on the reactions, the underlying nass transfer effects were not detailed and in most cases reaction rates were assumed to be much faster than mass transfer rates. The study by Keller and Giddings (1960) Hwang et al (1988) presented a detailed mathematical development for general combined separation-reaction processes. Unfortunately, multicomponent equilibrium theory does not consider mass transfer effects, which are usually important for large molecules (Kirkby et al, actions in fixed beds and observed shifts in solute retention due to irreversible reaction.…”

Section: Current Status Of Reaction-separation Modclingmentioning

confidence: 99%

Effects of protein aggregation in isocratic nonlinear chromatography

et al. 1991

View full text Add to dashboard Cite

Section: Current Status Of Reaction-separation Modclingmentioning

confidence: 99%

Effects of protein aggregation in isocratic nonlinear chromatography

et al. 1991

View full text Add to dashboard Cite

“…Most of these authors are focused on the derivation of mass balance equations, their applicability in computer codes, or special case studies. Very few papers [Hwang et al, 1988; straints on the rate laws. For the sake of simplicity it will be furthermore assumed that there is no immobile water.…”

Section: Introductionmentioning

confidence: 99%

Properties of concentration waves in presence of nonlinear sorption, precipitation/dissolution, and homogeneous reactions: 1. Fundamentals

Schweich¹,

Jauzein²

1993

Water Resources Research

View full text Add to dashboard Cite

Properties of concentration waves of solutes affected by nonlinear sorption, precipitation/ dissolution and homogeneous reactions in the mobile and stationary phases are established when the number of phases is constant. These properties essentially depend on the structure of a stoichiometric matrix which describes the chemical interactions. A reduction procedure of the stoichiometric matrix gives the number of waves or peaks together with their propagation velocities, and the retardation factors of species at trace levels. The location of the peaks and their broadening behavior due to the nonlinear equilibria are estimated. The number of waves and the properties of suitable linear combinations of concentrations provide a method for discriminating among rival interaction mechanisms irrespective of the equilibrium constants. This cannot be done using conventional methods based on the comparison between numerical simulations and experimental curves. Bryant et al., 1986] are devoted to the consequences of the set of elementary interactions (homogeneous reactions, adsorption and/or exchange reactions, precipitation, dissolution, degassing processes, etc.) on the structure and properties of the corresponding breakthrough curves (BTC).Predicting qualitative properties of BTCs or elucidating the main features of an interaction mechanism from experimental BTCs can be performed using numerical computer codes. Unfortunately, these calculations can be time consuming and they require that the interaction parameters (i.e., equilibrium constants, kinetic constants, etc.) be known.There is thus a need for some general properties relating the structure (i.e., shape, number, and existence of waves or peaks) of the BTCs to the structure of the solid-fluid interaction mechanism. These properties should be as independent as possible of the interaction parameters, and they should help one both to discriminate among rival mecHanisms and to estimate the sensitivity of the shape of the BTCs to physicochemical parameters. This first of two papers describes the underlying concepts used to achieve this goal. We begin by reviewing the concept used for the formulation of a speciation problem, and by defining a general "reduction procedure" which is the key point in the method described in this work. Subsequently, the solute transport model is presented assuming instantaneous equilibrium in a nondispersive steady flow. Finally, this model is used to derive the general properties of the BTCs resulting from a given solid-fluid interaction mechanism. In paper 2 [Schweich et al., this issue] these theoretical properties are compared with BTCs calculated with the computer code IMPACT, which allows one to simulate BTCs for any type of interaction, whether it be homogeneous or heterogeneous. ASSUMPTIONSTo focus our attention on the consequences of physicochemical interactions it will be assumed that water flows at a constant velocity and that the porous medium is isothermal. The behavior of reactive species will be accounted for by a "phenomenologic...

show abstract

“…The procedure to calculate the concentration profile is simpler and faster than with the above mentioned numerical models, largely because general properties of the solution of the problem are derived from mathematics rather than left to be found by the computer (Schweich et al, 1993). This way of proceeding has been used successfully in the field of chemical engineering (Helfferich, 1967;Hwang et al, 1988) and environmental sciences (Charbeneau, 1981(Charbeneau, , 1988Bryant, 2000, Prigiobbe, 2012a, 2012b. The purpose of this paper is to demonstrate its potential in the latter field, i.e.…”

Section: Introductionmentioning

confidence: 99%

Advective Transport of Interacting Solutes: The Chromatographic Model

Gruber¹

1996

Sediments and Toxic Substances

View full text Add to dashboard Cite

Species on porous media surfaces exposed to aqueous solutions can still not yet be determined unambiguously. The influence of these ambiguities on contaminant transport needs to be understood. Here methods of multicomponent chromatography are presented that allow to visualize the effects of the ambiguities. The Riemann problem is solved to a large extent based on the mathematics of non-linear hyperbolic differential equations, before the problem is handed over to the computer. Since thereby the computational efforts are kept compatible with the corresponding limitations in a chemical laboratory, this method has been used for decades in chemical engineering. The method is illustrated for various multicomponent isotherms, e.g. the one underlying surface complexation models as implemented in the MINEQL family of programs.

show abstract

Multicomponent equilibrium theory for ion‐exchange columns involving reactions

Cited by 16 publications

References 26 publications

Effects of protein aggregation in isocratic nonlinear chromatography

Effects of protein aggregation in isocratic nonlinear chromatography

Properties of concentration waves in presence of nonlinear sorption, precipitation/dissolution, and homogeneous reactions: 1. Fundamentals

Advective Transport of Interacting Solutes: The Chromatographic Model

Contact Info

Product

Resources

About