Fluid dynamics of differential circulation reactors using different mixers and designs

In many cases, the chemical kinetic examination of heterogeneous gas catalytic reactions is conducted by means of differential circulation reactors with internal mixing. This reactor should be gradient-free and behave like an ideally stirred vessel. A condition is ideal mixing, which is achieved via large circulation ratios. This paper deals with conducting, analyzing and re-calculating retention time distributions in order to determine the circulation ratios of four experimental reactors using different mixers and designs. The results show that adaptation of the model of an ideal tubular reactor with circulation results in a good correlation with the measured progress and courses, and that an adequate circulation ratio under the more stringent tests conditions applied here can only be achieved within a very limited parameter range. That means that the fluid dynamic behavior of the reactor should be known before making any kinetic measurements in order to avoid distortions of the measured data.