I have performed the adsorption studies and applied Langmuir model to the data. I obtained KL value from it. In literature it is given higher the KL value stronger the interaction between adsorbent and adsorbate. But there isn't any specific value of KL given.
In literature FTIR and XRD are also performed to predict the adsorption mechanism. I have done that as well and there is shift and change in the peak intensities.
Which one is better to predict the adsorption mechanism? Either from KL value or FTIR/XRD?
Noor Ul Ain
If you have adsorption from a solution, then the Langmuir isotherm is derived using the thermodynamic method. The thermodynamic method does not provide adsorption specificity. The method says that adsorption into one monomolecular layer occurs due to physical adsorption or chemisorption.
https://en.wikipedia.org/wiki/Langmuir_adsorption_model
KL characterizes the equilibrium constant of the reaction, that is, the equilibrium bias towards adsorption. You can determine the binding specificity by comparing the peaks of the IR spectra of the adsorbate in the solution and on the surface of the adsorbent.
From D-R model u can consider physical adsorption or chemisorption, When E
Yuri Mirgorod Thank you for your guidance.
Can I say it from shift or appearance of new peaks in IR spectrum that possible interaction is either chemisorption? or from XRD?
yes obviously, after chemisorption, IR spectra shifted to higher frequency data and XRD analysis gave less crystalline phase.
Noor Ul Ain
I wrote, if there is a shift of peaks of some functional group, then you can discuss this chemisorption. That is the same for XRD, but I am not sure that crystallinity will change. Perhaps Asma Siddiqa right about less crystalline phase in nanoparticles after adsorption of molecules. .
From the D-R model, u can consider physical adsorption or chemisorption; when E
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