Distillation Lines versus Residue Curves for a Mixture of Oxygen, Argon, and Nitrogen at 1 atm

Consider a ternary mixture composed of nitrogen, oxygen, and argon. This Demonstration compares the residue curve (dashed red) and the distillation line (dot-dashed blue). These two curves correspond to the composition profiles in packed (residue curves) and staged columns (distillation lines) at infinite reflux. You can drag the locator to change the position of the curves. This is a cryogenic process, with the temperatures in the diagram varying between 77.4 K and 90.3 K, the boiling temperatures of nitrogen and oxygen, respectively.