Pore Size Distribution of Carbon with Different Probe Molecules
Keywords:Activated carbon, GCMC, Monte Carlo simulation, pore size distribution.
In this study, a Grand Canonical Monte Carlo simulation (GCMC) method is used to study the adsorption of different probe molecules on activated carbon, while the experimental tests are performed by using a Gravimetric Analyzer. In addition the simulation results together with the measured isotherm data are used for the determination of micropore size distribution. Nitrogen at 77 K and carbon dioxide at 273 and 300 K are proposed as molecular probes. The simulation results obtained for various pore sizes represent the structure of molecular probe packing in the individual pores at different pressures. The reconstructed adsorption isotherm obtained by using these results and a postulated pore size distribution (PSD) function is used to determine the PSD of activated carbon which provides the best match between the simulation isotherm and the experimental isotherm. The PSD obtained using the GCMC agrees very well with the Density Functional Theory (DFT) method. The PSD for carbon dioxide differs from that for nitrogen due to the molecular structure and size. The advantage of GCMC is that it can provide not only adsorption isotherm but also the snapshot that presents the mechanism inside the pore.
Authors who publish with Engineering Journal agree to transfer all copyright rights in and to the above work to the Engineering Journal (EJ)'s Editorial Board so that EJ's Editorial Board shall have the right to publish the work for nonprofit use in any media or form. In return, authors retain: (1) all proprietary rights other than copyright; (2) re-use of all or part of the above paper in their other work; (3) right to reproduce or authorize others to reproduce the above paper for authors' personal use or for company use if the source and EJ's copyright notice is indicated, and if the reproduction is not made for the purpose of sale.