Equilibrium and rate-based dynamic models are proposed for a laboratory-scale, fed-batch, packed distillation column that operates at sub-zero temperatures. The purpose of the column is to separate tetrafluoroethylene from a ternary mixture that also contains hexafluoropropylene and octafluorocyclobutane. The simulation results for both models indicate second-order type responses, with either increases or decreases from the expected steady-state values. It is recommended to build a start-up routine into the simulations. Experimental validation should also form part of future work.