Ammonolysis of ethanol on pure and zinc oxide modified HZSM-5 zeolites Original Research Article

Reaction between ethanol and ammonia have been studied on various zinc oxide modified HZSM-5 (Si/Al=225) catalysts under various conditions of temperature, C/N ratio of the reactants and their WHSV. Two pure zinc oxides were taken for the study. One was a highly active acidic form Z1 and the other was a stoichiometric non acidic zinc oxide Z2. The activity of the catalysts for ammonolysis reaction followed the order Z2⪡Z1⪡HZSM-5. However, for composite catalysts containing 10–40% Z1 on HZSM-5, the activity increased synergistically and became maximum (∼81% conversion of alcohol) for the catalyst 40% Z1/HZSM-5 and about 50% conversion for the catalyst 40% Z2/HZSM-5. The products formed were mainly N-heterocycles. Some novel high molar mass N-heterocycles were also detected. The catalytic activity and product selectivity was crucially affected by the reaction conditions, particularly the effect of temperature; the optimum yield of the products was obtained at the catalyst temperature of 723 K, C/N ratio 0.3892 and WHSV of 2.5 h−1.