Investigate the adsorption of CO2/SO2 binary system on carbonaceous adsorbents by molecular simulation

In this work, adsorption of CO2/SO2 binary system on two types of carbonaceous adsorbents: 1) graphite and 2) adsorbent with cylindrical pore, is studied by grand Canonical Monte Carlo (GCMC) method. The number of adsorbed molecules and selectivity of SO2 molecule for different CO2 mole fractions are calculated and compared for two adsorbents. It is observed that cylindrical adsorbent has more selectivity than graphite. Also the effect of some important parameters such as temperature, diameter of cylindrical adsorbent, concentration of CO2 in the gas phase and existence of functional group on basal plane of graphite, is investigated on the selectivity of SO2. Results show that the selectivity of SO2 inside cylindrical adsorbent rises by increasing the mole fraction of CO2 in gas phase, also it reduces by increasing temperature and increasing the diameter of cylindrical pore size. In addition, the role of surface chemistry is studied by considering carbonyl group as functional group on the graphite surface. It is shown that the selectivity of SO2 is affected by carbonyl group.