Here q 0 i is the pure component isotherm, P is the total pressure, y i and x i are the gas phase and adsorbed phase compositions respectively, and i can be either CO 2 or N 2 . Finding a solution for (Eq. 15b) involves solving integrals. Mathematically, integrals can be solved either analytically, if the pure component isotherm has a functional form (q 0 i = f (P )), or numerically if it does not. Simon et al. developed a python package, Ideal adsorbed solution theory Python package (pyIAST), that supports both options. Pure component isotherms can either be fitted to thermodynamically consistent models such as Langmuir, Dual-site Langmuir, Quadratic, BET, Henry's law, and approximated Temkin, or be linearly interpolated in order to calculate the integral using numerical quadrature. In this work, we use the numerical option of pyIAST. The numerical option has the practical advantage that the outcome does not depend on the functional form that is used to describe the experimental or computational adsorption isotherm. This agrees with the work of Chen and Sholl , where they introduce a new Monte Carlo technique and combine it with IAST to avoid curve fitting.