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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.

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Iron modified zeolites of MFI structure, calcined at 873 and 1173 K, were doped with sodium cations in amounts corresponding to , , and to the total number of acidic centres, estimated from TPD of ammonia. Sodium modified Fe-ZSM-5(900) gradually lost their oxidative activity with an increase in the concentration of alkaline cations, while the activity of Na/Fe-ZSM-5(600) changed slightly and diminished considerably only after significant removal of acidic centres. The results of propane ODH reaction, performed at different contact times over alkaline free and alkaline modified Fe-ZSM-5 indicated, that oxydehydrogenation and cracking reactions on the samples calcined at 1173 K occurred as consecutive reactions, while in the presence of catalysts activated at 873 K, and characterised by strong acidic centres, both reactions occurred simultaneously.