Abstract Application of theoretical results obtained in Part I is demonstrated by dynamic modelling of the complex heterogeneous catalytic oxidehydrogenation of isobutyric aldehyde to methacrolein. The heteropoly acid H 5Mo 10V 2PO 40 is used as catalyst. Reactor inlet concentration step changes are realized by exchanging two feed streams of different composition with solenoid valves. Quasi-continuous measurement of reactant partial pressure transients is accomplished by mass spectroscopy. Based on dynamic experiments, a reaction scheme is proposed and estimation of kinetic parameters of the main reaction using an Eley-Rideal type rate equation is carried out. Limitations of dynamic modelling are discussed.