Semi-batch and batch experiments are conducted in series to investigate thermodynamic equilibria for reactor temperatures of 233 K, 243 K, and 253 K. For practical reasons, the reactor is first operated at constant pressure in semi-batch mode for 400 minutes before switching to batch mode and adjusting the pressure in a series of small step changes. Exemplary measurement runs of pressure and CO 2 fraction approaching equilibrium values are shown in Fig. in the ESI †.