Pure and modified layered double hydroxides (LDH), modified ZSM5 zeolites, and new type of Raney Ni (RNi) catalysts were tested in reactive distillation of glycerol (byproduct of biodiesel production). The favorable reaction is dehydration followed by hydrogenation. The dehydration basically occurred via ionic pathway, but some catalyst can initiate radical processes, resulting higher conversion, but lower selectivity. If Ni is in ionic form, the formation of radical products, such as acetaldehyde (ZSM5) and allyl alcohol (LDH) is characteristic. With increasing metallic character, RNi promote also the formation of acetol. The Cu- and Cr inhibit the radical processes, resulting in formation mainly acetol (HT) and acrolein (ZSM5). 1,2-propanediol formation was detected just in the reaction over pure HT and Mg-Al mixed oxides, albeit with low yield. On the other hand the selective (∼90%) production of acetol was obtained in the presence of Cu and Cr containing HT. The XRD patterns and BET measurements of the catalysts indicated irreversible changes in their structures during the reactive distillation.