CO2 and SO2 Capture by Cryptophane-111 Porous Liquid: Insights from Molecular Dynamics Simulations and Computational Chemistry

A computational study of the encapsulation of a gaseous mixture of CO₂ and SO₂ in a Type II porous liquid is performed under different conditions. The system is composed of cryptophane-111 molecules dispersed in dichloromethane, and it is described using classic molecular dynamics at atomistic resolution. Gaseous CO₂ tends to almost fully occupy cryptophane-111's cavities during the first phases of simulation, and, afterwards, it is surpassed by SO₂'s tendency for occupation. Calculations are performed at five different temperatures in the range of 273 K-310 K, finding a positive correlation between SO₂ adsorption and temperature. An evaluation of the radial distribution function of SO₂ and CO₂ with respect to cryptophane-111 is employed to quantify the number of captured molecules, and an energy study using Density Functional Theory methods is also performed to evaluate the relative stability of the two gases inside the porous liquid.