The Simulation Of Complex Dynamics Of N₂O Decomposition Over Cu-ZSM-5and The Theoretical Research Of Mechanism For No Promoting N₂O Decomposition

The phenomenon of N2O decomposition over Cu-ZSM-5has been observed on the experiment, the research of the oscillation theory can help to explain the kinetics of N2O decomposition over Cu-ZSM-5and as well benefits to the kinetics of the reaction over zeolite molecular sieve catalyst. The noise is unavoidable in the reaction of N2O decomposition over Cu-ZSM-5and the observation from experiment is related to it, so the requirement of the oscillation and the effect of noise had been studied in our research. By the steady analysis of the elementary reaction function, the trace of Jakob matrix can confirm the property of the system. According the results from the experiment the activation energy of the step2in elementary reaction is the function of the Cu+coverage degree. It is required to combine the activation energy and the Cu+coverage degree, which leads to the trace of Jokob matrix change sign and the oscillation happens. The system state changes as the control parameter and the Hopf bifurcation arises. Besides the term of oscillation the external noise has been added in the system by means of adding the external noise term in the kinetic fuction. The effect of external noise with different intensity to the system has been studied and the results show that there is a suitable noise intensity which benefits to the oscillation. In addition to external noise, the internal noise has also been added to the system. When the control parameter near Hopf bifurcation point the internal noise take an important role, so at this condation the internal noise has been studied. At different system size the internal noise cause different results and the power spectrum analysis and signal to noise show the happening of system size resonance. The internal noise also take the positive effect to the system. At last the effect of NO promoting N2O decomposition has been studied over single copper ZSM-5catalyst. The two possible pathways have been provided and the energy barrier has been calculated by density function method. According to the calculation results the NO effect in the two pathways has been discussed.