PERIODIC PERTURBATION OF A DRIFTING HETEROGENEOUS CATALYTIC-SYSTEM

The investigation of the dynamic behavior of chemical systems by experiments can be seriously impeded by a drift of variables. Sometimes, this drift is taken advantage of by considering it as an autonomous change of a bifurcation parameter. As an example, this approach is applied to the dynamic behavior of the oscillatory oxidation of formic acid over Pd/Al2O3. The system is driven with a periodic variation of there actor temperature with constant frequency and an amplitude of just 0.25 K. With the catalyst temperature changing autonomously, a drift from quasi-periodicity through various entrainment bands is observed. It is shown through a simulation with the simple circle map that this experiment is essentially equivalent to a classical entrainment experiment. A phase multistability is observed within the 1:1 entrainment band which is reminiscent of the behavior of an extended sine map.