Isotherm models for reverse phase

Hi Everyone, I am trying to model reverse-phase chromatography in CADET. I would like to use the LDF model with multi-component Langmuir and/or anti-Langmuir isotherm. The isotherm parameters vary as a function of modifier concentration. Is there any way we could customize for this type of problem? I am referring to the following paper Getaz et al., Journal of Chromatography A, 1284 (2013) 69– 79. Thank you.

Hi and welcome to the CADET-Forum!

We have a Langmuir Isotherm with Mobile Phase Modulator. Maybe this already helps?

Regardless, could you post the equations here, please?

While we have LDF versions of the multi-component Langmuir model, there is currently no direct implementation of the LDF versions of the mobile phase modifier Langmuir model. However, you can make the isotherm parameters of the existing implementation depend on an external function, which should provide a workaround for your case.

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Thank you Eric, for your quick reply and suggestion. Could you please point me to the relevant example where isotherm parameters are calculated in an external function and use modifier concentrations? Also, is there any workaround for LDF model with Moreau isotherm?

Thank you Johannes for quick reply. Here is the Moreau isotherm q= q_s^*\frac{k_1 C+k_1 C^2 I}{1+2 k_1 C+K^2 C^2 I} and k_1, k_2, I are a function of C_{modifier}.