Enhancement of the catalytic activity of H-ZSM-5 zeolites for glycerol acetalization by mechanical grinding

The synthesis of 2,2-dimethyl-1,3-dioxolane-4-methanol (solketal) from acetalization of glycerol with acetone was carried out over two types of ZSM-5 zeolites of similar Si/Al ratio (=12.5 and 13.5) characterized with different particle sizes. The reaction was performed in a liquid phase, under mild reaction conditions. The applied samples showed very different glycerol conversion depending on the particle size of the catalysts. Using large particle materials results in relatively low activity in the studied reaction due to the long diffusion way of substrates and products. The modification of commercial zeolites by means of grinding results in the formation of fine agglomerates and brings about a significant increase in solketal yield.