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Publisher Summary The regenerative catalytic oxidizer (RCO) technology has evolved significantly as an efficient method to control volatile organic compounds. The RCO technology favors using oxide catalysts because it allows for easy compensation of lower activity by an increase in the catalyst amount or temperature. Heat transfer and accumulation properties of ceramic packing material strongly influence RCO performance. The rate of heat transfer affects the temperature gradients along the bed length that, in turn, determine the volume of material required to preheat the gas to the temperature of catalytic or thermal oxidation. During the catalyst operation, it gradually becomes less active and must be eventually replaced. The factors affecting the catalyst lifetime include high temperature, catalytic poisons, and masking agents. Compounds of halogens and sulfur are the most common catalyst poisons. Temperature control, poison tolerant catalysts, and gas-flow pretreatment are used to reduce the impact of catalyst deactivation. This chapter also presents the behavior of an RCO when the catalyst deactivates, and proposes strategies ensuring the required performance during the entire catalyst lifetime.

The paper discusses the development of catalytic converter for aftertreatment of exhaust gas from diesel engines powered with natural gas. The converter, operated with periodical reversals of the flow, ensures destruction of CO and hydrocarbons, including methane. Both computer simulation and engine testing results are presented.

Publisher Summary Interaction of the dynamic properties of a catalyst, a micro-scale physic-chemical system, and the dynamic properties of the macro-scale reactor creates an opportunity to improve the performance of catalytic processes using forced unsteady-state operation. Forced dynamic operation makes it possible to generate spatio-temporal patterns of temperature, composition and catalyst states that cannot be attained under steady-state operation. Probably, a potential for increase of efficiency of partial oxidation processes due to FUSC is tremendous. Frequently observed small effects apparently result from current research philosophy: trial-and-error experimentation with different forced periodic regimes while searching for drastic improvement. Money should be spent for elucidation of the process mechanism, developing models appropriate for numerical simulation, search for optimums using computer simulation, then testing the results in the lab or pilot unit.