Study of Pb2+ adsorption in a packed bed column of bentonite using CFD

In this study, experiments and CFD (Computational Fluid Dynamics) simulations were conducted to investigate lead ion (Pb2+) adsorption in bentonite. Experiments were carried out in a fixed bed column at 30°C, pH = 4.0 and average particle diameter of 0.127 mm. The influence of the flow rate on the breakthrough curves was examined with constant inlet concentration equal to 0.88 meq L-1. The CFD technique was used for the simulation of flow patterns and ion concentration profiles inside the fixed bed column during the adsorption process. A 2D axisymmetric model based on Navier-Stokes and diffusion-convection equations was used for simulating the fluid phase. Experimental data obtained for different inlet flow rates and Pb2+ concentrations were used for validating the model. The CFD simulations predicted the experimental behavior of the fixed bed adsorption very well in all conditions under study.