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Numerical Approximation of a Nonequilibrium Model of Gradient Elution Chromatography Considering Different Functional
Arif Mahmood1, Muhammad Uzair1, Sadia Perveen1,2
1Department of Mathematics, COMSATS University, Park Road, Chak Shahzad, Islamabad 45550, Pakistan.
ACS Omega
|May 13, 2024
Summary
This study analyzes how solvent composition affects separation in gradient chromatography. Optimizing mobile-phase composition enhances column efficiency and selectivity, reducing processing times.
Area of Science:
- Analytical Chemistry
- Chemical Engineering
Background:
- Gradient chromatography utilizes mobile-phase composition changes to improve separation.
- Optimizing solvent gradients is crucial for efficient chromatographic processes.
Purpose of the Study:
- To theoretically investigate the impact of solvent composition on elution profiles in fixed-bed liquid chromatography.
- To quantify the effects of various gradient parameters on separation performance.
Main Methods:
- A lumped kinetic model coupled with the convection-diffusion equation was employed.
- Nonlinear model equations were solved using a semidiscrete second-order finite-volume method.
- Numerical solutions were used to analyze concentration profiles and temporal moments.
Main Results:
- Varying solvent compositions significantly influence retention characteristics and elution profiles.
- Gradient parameters like starting/ending times and slope affect concentration profiles.
- The study quantified the relationship between solvent strength and gradient profile.
Conclusions:
- Optimizing solvent composition and gradient parameters enhances separation efficiency and selectivity in chromatography.
- This research provides a theoretical framework for improving gradient elution chromatography processes.
- The findings contribute to reduced recycling times and increased throughput in chromatographic separations.
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