Catalytic Synthesis of 2-Methyl Pyrazine Over Zn-Modified Zeolites

Cyclization of ethylene diamine and propylene glycol to 2-methyl pyrazine (2-MP) was investigated on Zn-modified zeolites, namely ZSM-5, Beta, and ferrierite catalysts, as a function of temperature, space velocity, and feed ratio. Zn-impregnated ZSM-5 was found to be the promising catalyst with 64% selectivity for 2-MP at 450 °C. ZnO-like species on Zn-impregnated ZSM-5, identified from XPS, enhance the selectivity to 2-MP. The difference in acidity, the nature of the Zn species, and its distribution on Zn-modified ZSM-5 catalysts obtained from FT-IR and XPS are in good agreement and they are correlated with catalytic activity.