Pulse microreactor examination of the vapor-phase aldol condensation of acetone

Pulse microreactor techniques and a small flow reactor have been employed to examine the nature of the MgOAl2O3-catalyzed aldol condensation of acetone to principally mesityl oxide and isophorone. It has been shown that a large number of transient intermediates are involved in a series of very rapid, reversible equilibria. The last step in this sequence is the irreversible formation of isophorone which appears to be the net driving force of this condensation reaction. The nature of the catalyst, the effect of various additives, and the reaction intermediates and by-products have been detailed in order to arrive at an overall description of the base-catalyzed oligomerization of acetone.