Modeling of the adsorption rate of geniposide on granular adsorbent under different conditions considering several mass transfer mechanisms

This study presents a novel modeling approach to investigate the adsorption kinetics of geniposide (GS) in a batch solid-liquid system. The model incorporates both external and internal mass transfer resistances and is based on mass conservation of the adsorbate. A system of kinetic partial differential equations (PDEs) is developed to describe transport phenomena in both the liquid and solid phases within the adsorbent particle. The model considers the effects of initial GS concentration, solid/liquid volume ratio (SLR), and temperature on adsorption performance. Predictions of GS concentration profiles and the mass transfer zone (MTZ) evolution in a 3D spherical geometry show good agreement with experimental data, confirming the model's ability to capture adsorption kinetics and mass transfer mechanisms. This approach provides a comprehensive understanding of solid-liquid adsorption systems, offering a robust framework for future studies in chemical engineering.