Beyond Freundlich and Langmuir: the Ruthven–virial equilibrium isotherm for aqueous-solid adsorption systems

It is the purpose of this paper to investigate data fitting attributes exponential integral isotherm, which was first derived by Ruthven in 2004 describe adsorption at gas–solid interfaces. The a variant virial incorporates two parameters Langmuir isotherm and has an expandable mathematical structure. lain dormant for nearly 20 years. This fact may seem surprising considering versatility as will be shown work. A slightly modified form called Ruthven–virial used work interpret previously published aqueous-phase data. observed that capable accurately tracking experimental isotherms with without apparent plateau. Freundlich good describing plateau, while excels combines individual strengths into single model. Furthermore, it performance two-parameter comparable three-parameter Sips isotherm. hidden gem practical alternative equations correlation hyperbolic isotherms. We hope findings presented here inspire research community evaluate modeling contaminant aqueous-solid