Performance of a continuous Taylor-Couette-Poiseuille vortex flow enzymic reactor with suspended particles

Vortex how reactors (VFRs) are a good option when fragile particles are pre sent in the medium, due to their gentle but efficient stirring characterist ics. However, the presence of a by-pass stream may deteriorate the reactor performance, and particles of inadequate density may either settle down or clog the reactor outlet. This work assessed the performance of an enzymic V FR. Fructose-glucose isomerization, catalyzed by immobilized glucoisomerase was the test reaction, taking advantage of the negligible changes that it causes on the medium viscosity. Intra- and extra-particle mass transfer eff ects were avoided. Reactor geometry (radius ratio eta = 0.677 and aspect ra tio Gamma = 18.30) and residence time were selected aiming at possible appl ications of the device as a bioreaction and/or adsorption system. Visualiza tion experiments confirmed that the vortices' cores stop their axial displa cement when the rotation of the inner cylinder is increased. Intermediate r otations were the most detrimental to reactor performance, due to by-pass e ffects. Vortex agitation is very gentle, causing no detectable damage to sh ear-sensitive particles. (C) 2000 Elsevier Science Ltd. All rights reserved .