Regardless of the initial gasphase composition of the reactor, the system approached a dynamic steady state of 70 mol% B in the gas phase. While the small oscillatory behavior is difficult to observe in Figure , oscillation in the instantaneous TOF B was observed upon zooming in on any of the data sets. Once the catalyst was converted from dynamic to static operation at 200 s, the system returned to thermodynamic equilibrium at 40 mol % B (ΔH ovr of +2 kJ/gmol), indicating that deviation from equilibrium resulted from dynamic 'catalytic pumping' on the catalyst surface.