MIXING EFFECTS IN VARIABLE-VOLUME CHEMICAL REACTORS

Periodic or semibatch operation of a continuous stirred reactor produces levels of mixing on the macroscale which are intermediate to the limits of plug flow and stirred tank operation and which can be selected and controlled to any desired level. Such a scheme is an operational alternative to the tanks-in-series or plug flow with recycle system, and provides a means of experimentally producing a desired mixing level or of increasing the yield of desired intermediates in complex reaction schemes. In this work criteria for obtaining desired mixing levels are presented, the resulting degree of segregation, J, is derived, and the influence of segregation or conversion for a second-order reaction is presented. Comparisons to the more familiar tanks-in-series and recycle-plug-flow models are included. © 1979, American Chemical Society. All rights reserved.