Figures and show the effect of truncating the CO 2 isotherm on CO 2 IAST predictions keeping the N 2 pure component isotherm intact (left), as well as the effect of truncating the N 2 isotherm on N 2 IAST predictions keeping the CO 2 pure component isotherm intact (right) for a mixture of 10% and 90% CO 2 , respectively. It is evident from both figures that, if the pure component isotherm of component i is truncated at a pressure higher than P 0 i , the IAST predictions are exact and the relative error is always null. This follows from the definition of equation 19. Nevertheless, if the truncated pressure lies to the left of P 0 i , the pure component isotherm looses "important information"" and pyIAST's extrapolation leads to incorrect mixture predictions. Also, the further we truncate to the left, the higher the relative error. In fact, there is an exponential correlation between the relative error and the truncated pressure. Relative Error (%)