NITROGEN ADSORPTION IN SLIT PORES AT AMBIENT-TEMPERATURES - COMPARISON OF SIMULATION AND EXPERIMENT

We have used GCMC simulation to study the adsorption of nitrogen into silt-shaped micropores at 303 K. Nitrogen was modeled as a one-center or as a two-center molecule, with or without quadrupoles. The pores we re modeled as parallel smooth graphite surfaces. Pore widths, correspo nding to two samples of activated carbon fiber having internal pore wi dths of 0.75 and 1.45 nm, were selected. The carbon to carbon distance H, needed in the potential energy calculation, was found from geometr ical parameters. Two alternative methods of calculation of this quanti ty are discussed. Better agreement with experiment is obtained if H is based on the minimum of the interaction potential rather than the thi ckness of graphite plane. Differences between the one-center and two-c enter models were found in the smaller pore and can be attributed to t he different packing available to the two models.