This article presents a multi-scale simulation approach starting at the molecular level for the adsorption process development, especially, in o-DCB (ortho-Dichlorobenzene) adsorption on an activated carbon. A grand canonical Monte-Carlo (GCMC) method is realized by using Materials Studio v. 4.2 with the Forcite and the Sorption modules (Accelrys Inc., USA) in the molecular level. In this molecular simulation, adsorption isotherms and kinetic parameters are calculated.

Computational fluid dynamics (CFD) can show the velocity and concentration profiles of the fluid phase within the adsorption column. Using COMSOL Multiphysics v. 3.3 (COMSOL AB., USA) as a CFD code, the characteristics of the fluid is identified according to the column geometry.

After the model parameters of the adsorption process simulation are estimated from, the process simulation is performed for the operating condition optimization or the process design, using these model parameters estimated from the molecular-level and the fluid level. In the process simulation level, the process simulation is performed in FAST-Chrom/SMB (Fast and Accurate Simulation Tools for Chromatography and SMB), which developed by our own laboratory.

The simulation results obtained from the adsorption equilibrium constant predicted at the molecular level are in good agreement with the experimental results of a pulse response. The systematical multi-scale simulation approach addressed in this study may be useful to accelerate the adsorption process development in reducing the number of experiments.

Keywords: Multi-scale simulation, Molecular simulation, Process simulation, Activated carbon, Adsorption isotherms, Computational fluid dynamics (CFD).