Heterogeneous process stationary states

Michel Boudart, Kinetics of Chemical Processes, Prentice-Hall, Inc., Englewood Cliffs, N.J., 1968. A concise presentation of the fundamental concepts of kinetics for homogeneous and heterogeneous reactions, including a chapter on the application and validity of the stationary-state hypothesis. 

It is the occurrence of a fast steady-state branched-chain reaction that enables to realize a noncatalytic gas-phase process and create a stationary technological process on its basis. The quasi-steady-state branched-chain mode provides a high rate of a noncatalytic reaction at relatively low temperatures, whereas the absence of a solid phase (catalyst) minimizes the influence of heterogeneous processes, which lead to the formation of deep oxidation products. In addition to the critical transition between the oxidation modes, other manifestations of the nonlinear nature of the process, such as cool flames, NTC region, reaction rate temperature hysteresis, and oscillatory regimes, have been observed. 

Figure 1.4. Flow chart sheet of the strategy of bioprocess kinetic analysis for different process situations stationary/instationary, homogeneous/heterogeneous, differential/ integral, and true dynamic/balanced (frozen) reactor operation, rds, rate-determining step qss, quasi-steady-state, (From Moser, A. 1983.)...

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