Comments on "Glycerol conversion to acrylonitrile by consecutive dehydration over WO3/TiO2 and ammoxidation over Sb-(Fe,V)-O", published by Liebig, C., Paul, S., Katryniok, B., Guillon, C., Couturier, J.-L., Dubois, J.-L., et al. in Applied Catalysis B: Environmental, 132-133 (2013) 170-182. doi:10.1016/j.apcatb.2012.11.035