ZnO-based catalysts on Al2O3 as support are prepared and modified with different metal elements through impregnation, and first applied in synthesis of pyrazinyl compounds from glycerol and 1,2-propanediamine (PDA) in the present work. The results indicate that the produced pyrazinyl compounds mainly include 6-hydroxymethyl-2-methylpyrazine (6-HMP), 5-hydroxymethyl-2-methylpyrazine (5-HMP), 2,6-dimethylpyrazine (2,6-DMP) and 2,5-dimethylpyrazine (2,5-DMP). Characterization results show that ZnO species in catalysts provide acid-base pairs (Zn2+-O2-), catalysts modified by Ce, Ca, Mn and Mo exhibit spillover phenomenon of hydrogen. According to the effect of Zn amount and modification on the physicochemical and catalytic property of ZnO-based catalysts, the cyclization pathway of glycerol with PDA is proposed. The formation of 2,6- and 2,5-DMP is thought to directly take place over acid sites through glycerol dehydration and further cyclization with the activated PDA, also through hydrodehydration of 6- and 5-HMP, respectively. 6- and 5-HMP are mainly produced by the interaction of activated PDA molecules on acidic sites with dihydroxypropanal or dihydroxyacetone from glycerol dehydrogenation on basic sites. (C) 2013 Elsevier B.V. All rights reserved.