A Simple Mechanistic Multilayer Model for the Rigorous Description of Brunauer–Emmett–Teller Type Isotherms

Abstract

The rigorous description of adsorption isotherms of gases or vapors on solids is of major interest for analytical methods such as chromatography and adsorbent-based separation processes (e.g., PSA). In the specific case of a multilayer adsorption mechanism, a complex isotherm pattern is obtained, which is most often described on the basis of the well-known Brunauer–Emmett–Teller (BET) model. However, large discrepancies between experimental data and BET model fitting occur for some systems. We report here a new simple mechanistic approach that takes into account the formation of multilayers. The resulting expression involves two parameters and shows an excellent fit compared to BET when applied to an experimental data set. The interest in the model for adsorbent characteristic determination and process simulation studies is discussed.

4‐OH‐TEMPO radical grafted onto a novel polyaromatic ether sulfone containing carboxyl side chains as solid catalyst for alcohol oxidation

“…In the low P / P 0 range, the adsorption capacity of the three samples corresponded to monolayer adsorption. With further increasing the relative pressure, the adsorption of nitrogen increased linearly 41 . At the high P / P 0 stage, the catalyst samples showed multilayer adsorption, and the adsorption capacity gradually changed.…”

“…With further increasing the relative pressure, the adsorption of nitrogen increased linearly. 41 At the high P/P 0 stage, the catalyst samples showed multilayer adsorption, and the adsorption capacity gradually changed. As listed in Table 3, after grafting, the specific surface area of polymer declined from 34.6 to 13.1m 2 /g.…”

The Jovanović adsorption isotherm in water contaminant research: Unmasking spurious versions and spotlighting the real thing

“…Furthermore, Eq. ( 2) was obtained by Schaetzel et al (2017Schaetzel et al ( , 2021 using a generalized Henry's law that does not depend on molecular collision assumptions. Nevertheless, there are some similarities in the methods used by Schaetzel et al (2017Schaetzel et al ( , 2021 and Misra (1980).…”