OXIDATIVE DEHYDROGENATION OF ETHANE OVER LANTHANA - ACTUAL NATURE OF THE ACTIVE PHASE

Characterization studies of lanthana before and after running the oxidative dehydrogenation of ethane (OXDE) on lanthana show the "in situ" transformation of La2O3 in hexagonal La2O2CO3. Thermodynamic considerations, as well as the results of the catalytic activity essays carried out on an intentionally prepared La2O2CO3 sample demonstrate that, under the experimental conditions used, type II lanthanum mono-carbonate dioxide phase constitutes the actual active phase. This may explain the differences of catalytic activity observed between lanthana and several other rare earth sesquioxides. © 1990 J.C. Baltzer A.G. Scientific Publishing Company.