Effect of Strong Sample Solvent on the Solute Dynamics for More or Less Viscous Sample: A Comparative Study

The flow dynamics of the adsorbed solute is studied under the influence of viscosity contrast between the localised solvent and the displacing fluid. This viscosity contrast leads to viscous fingering at either of the interfaces of the solvent. Alongside, the solute dynamics is getting affected by its solvent modulated adsorption also. To explore the effect of this physico-chemical phenomena on the broadening of the multiphase solute, we present a comparative study of unstable frontal and rear interface of sample having eluting strength larger than the displacing fluid. The study showed that viscous fingering at the frontal interface of the sample solvent combined with the solvent strength, intensifies the band broadening of the solute zone. Whereas, it counteracts when the viscous fingering is at the rear interfce of the sample solvent. A comparative study is performed to analyze the degree of mixing which shows that the less viscous sample leads to faster mixing of adsorbed solute in comparison to the more viscous one.