关键词: axial dispersion model;open reactor;residence time distribution;effect of background reactant

Abstract: The paradox is well known that the residence time distribution(RTD)is not valid forthe estimation of the conversion of a first order reaction in an open tubular reactor.A casc ofδinjection of reactive species into an open flow system is investigated theoretically in this paper.The analytical solution with the Laplace transform demonstrated that the conversion of a first orderreaction is identical to that in a closed reactor under steady state.The effect of the backgroundreactant concentration gradient addressed by the authors in a previous paper was employed to thiscase.and the numerical solution of the tracer dispersion based on this novel argument gave rise to asimilar value of conversion.suggesting the validity of the concept and the significance of the subtledifference between RTDs determined with or without the presence of a background reactant in anopen flow system.

Key words: axial dispersion model, open reactor, residence time distribution, effect of background reactant