(260a) On the Use of the Dual Process Langmuir Model for Gas Mixture Components That Exhibit Single Process or Linear Isotherms

There are two interesting cases that arise when one of the components in a gas mixture is described by either the single process Langmuir (SPL) model or the linear isotherm (LI) model and the other component is described by the dual process Langmuir (DPL) model. These two cases are very subtle and have never been addressed in the literature.

For the first case, a methodology will be presented based on three approaches to predict the mixed gas isotherms of a binary system, wherein one of the components is described by the DPL model (usually the heavier component) and the other one is described by the SPL model (usually the lighter component). These approaches differ on whether the individual processes of the isotherms correlate in a perfect positive, perfect negative or indifferent fashion. For the second case, a methodology will be presented based on two approaches to predict the mixed gas isotherms of a binary system, wherein one of the components is described by the DPL model (the heavier component) and the other one is described by the LI model (the lighter component). These approaches differ on whether the individual processes of the isotherms correlate in a perfect positive or perfect negative fashion. For both cases, a consistent set of single and binary isotherms from the literature that behave these ways are used as the basis for comparison to demonstrate these concepts.