ELASTIC Vα pore,molecule, AVERAGE DENSITY, LOCAL EFFECTIVE DENSITY FUNCTIONS AND THEORETICAL MONOLAYER TO RE-ACCESS CO2 ADSORPTION IN NaX ZEOLITE

This work presents three theoretical functions for obtaining nanoscale CO2 adsorption data on a dehydrated NaX zeolite reported in the literature at temperature (T) = 298 K, pressure (p) = 1 bar, ratio SiAl–1 = 1, BET equivalent area (SBET) = 652 m2 g–1, pore total volume (Vmp) = 0.43 cm3 g–1 and saturation capacity approximately 6.27 mmol g–1. From BET and Vmp, the theoretical monolayer capacity at 10 mmol g–1 was derived. Results indicate that the CO2 experimental saturation corresponds to 60% of the monolayer, reflecting the partial accessibility of adsorption sites. The analysis of the average density at this loading shows value approximately 0.65 g cm–3, finding a reasonable parallel of molecular packing inside BET pore comparable to saturated liquid state of CO2, 0.77 g cm–3 at 298 K, p = 65 bar. The benchmark points to values around 3.0-3.5 g cm–3 that corresponds to a forced solid state of CO2 obtained under high pressure. Therefore, this methodology supports the plausible interpretation of adsorbate-adsorbate of packing density at 114 ± 8.1 Å3 molecule–1. It was estimated in 6.55 the number of strong-active sites per α-cavity in cell of NaX and occupation of 1.62 CO2 molecules per adsorption sites in co-adsorption process.