INTERACTION OF ACETONE WITH AMMONIA AND ALCOHOLS OVER A HZSM-5 ZEOLITE .2. ETHANOL

The reactions of ethanol and ethanol + ammonia with surface species formed from acetone on a HZSM-5 zeolite were investigated and compared with those of methanol. The studies were carried out using temperature-programmed conversion of adsorbed reactants with mass spectrometric analysis of the products evolved and C-13 MAS NMR detection of surface species. It was found that ethanol alkylates the acetone surface species, whose decomposition increases the yield of propylene and especially aromatics in the products. The yield of aromatics is only slightly affected by the presence of ammonia, as was also observed for methanol+ammonia. This is considerably different from the reaction of ammonia alone with the surface acetone species. As the main product of the interaction of ethanol alone with the zeolite is ethylene, the reaction of ethylene with the acetone species was also studied. It was found that these two reactants, ethanol and ethylene, behave quite differently; the effects observed can thus be ascribed to the reaction of ethanol with the acetone species.