Studies of the Kinetics of Solute Adsorption at Solid/Solution Interfaces:  On the Possibility of Distinguishing between the Diffusional and the Surface Reaction Kinetic Models by Studying the Pseudo-First-order Kinetics

Abstract

It is shown that the popular pseudo-first-order Lagergren equation can be applied to correlate kinetic adsorption data only in the adsorption systems that are not far from equilibrium. Also, it is shown that the Lagergren equation is then the limiting form of the kinetic equations developed by assuming both diffusional and surface reaction kinetic models. However, the theoretical interpretation of the coefficients in the Lagergren equation is then different for the two different kinetic models. The comparison of the theoretically predicted values of these coefficients with their experimentally determined values creates a chance to conclude whether the diffusional or the surface reaction model should be assumed to represent the kinetics of adsorption in an investigated adsorption system.

On the applicability of the pseudo-second order equation to represent the kinetics of adsorption at solid/solution interfaces: a theoretical analysis based on the statistical rate theory

“…It was successfully applied to describe the rates of interfacial transports of various kinds. Very recently the SRT has been also used to describe the kinetics of solute adsorption at the solid/solution interfaces (Rudzinski and Plazinski 2006, 2007a, 2007b, 2008a, 2008b, 2008cAzizian et al 2008). Following SRT:…”

“…Recently we have shown that when the Langmuir model of adsorption onto a homogeneous surface is accepted, expression (2) takes the following form (Rudzinski and Plazinski 2007a):…”

“…This issue will be discussed in detail in the next subsection. The above discussed simple method of determining θ e value was successfully applied by us in our previous papers (Rudzinski and Plazinski 2007a).…”

Lagergren equation: Can maximum loading of sorption replace equilibrium loading?

“…E-mail address: tshahwan@birzeit.edu kinetic data in the adsorption systems that are not far from equilibrium (Rudzinski and Plazinski, 2007). The same study showed also that the equation can be the limiting form of the kinetic equations developed by assuming both diffusional and surface reaction kinetic models.…”

Kinetic analysis of the weak affinity interaction between tris and lysozyme

“…To resolve the kinetic parameter of the interaction between tris and lysozyme, the pseudo-first-order interaction kinetics which relates to the onestep simple reactions is introduced (see Eq. (1)) [25]. is delivered to the tris immobilized surface, which increases the sensor signal.…”