| Abstract
| - Oscillatory flow reactors (OFRs) are a novel type of continuous reactor, in which tubes fittedwith orifice plate baffles have an oscillatory motion superimposed upon the net flow of the processfluid. The combination of baffles and the oscillatory motion creates a flow pattern conducive toefficient heat and mass transfer while maintaining plug flow. Unlike conventional tubularreactors, where a minimum Reynolds number must be maintained, tube-side mixing isindependent of the net flow, allowing long residence times to be achieved in a reactor of greatlyreduced length-to-diameter ratio. We have evaluated a pilot-scale OFR as a method for continuousproduction of sterols in an ester saponification reaction. The OFR achieved the required productspecification, in a residence time one-eighth that of a full-scale batch reactor. To betterunderstand the effect of the process variables on the reactor performance, the OFR was modeledusing a tanks-in-series residence time distribution, combined with the saponification reactionkinetics, giving a “flow-conversion” model which predicted conversion based on flow and feedparameters. This simple model has led to a number of insights into the optimal operation of theOFR, one of which was that the OFR could give desired conversion selectivity at a lower reactiontemperature without significant alteration to other process variables. Also, the current productspecification could be surpassed, if necessary. These predictions were verified by experiment. Afull-scale OFR design based on these results would be less than one-hundredth the volume of afull-scale batch reactor, assuming the same production rate and product quality. The constructionof such an industrial-scale OFR for the saponification reaction is now being considered by anindustrial collaborator.
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