THERMAL-ACTIVATION OF TYPICAL OXIDATIVE DEHYDROGENATION CATALYST PRECURSORS BELONGING TO THE NI-MO-O SYSTEM

NiMoO4 obtained by calcination of precursors has been shown to be a very effective catalyst for oxidative dehydrogenation of propane into propene. Preparation conditions and thermal decomposition of two precursors have been studied by TG-DTA, HTXRD, FFT-IR, and thermo-desorption coupled to mass spectroscopy in order to determine their composition and to define the best treatment to favour the oxidative dehydrogenation process. The selectivity and activity for propane transformation into propene are very different depending on the nature of the precursor and of the active phases obtained after thermal activation. The more selective high-temperature beta phase of NiMoO4 has been obtained at a lower temperature (500-degrees-C) than previously reported (700-degrees-C).