Isothermal reduction behaviour of undoped and Ca-, K- and P-doped NiMoMO4 phases used for selective propane oxydehydrogenation

Isothermal reduction under hydrogen of polymorphic NiMoO4 system has been s tudied at different temperatures using thermogravimetry. Evidences found by TG (oxygen depletion rate) have shown a dependence on lattice oxygen mobil ity and source due to the crystal structure and temperature. Relative to the undoped NiMoO4 phases, it has been found that the presence of K2O, CaO and P2O5 promoters simultaneously affects both the reduction ra te and the oxygen source. Monolayer lattice oxygen mobility of undoped and doped NiMoO4 material was investigated by oxydehydrogenation of light alkanes performed by using a pe riodic flow micro-reactor. The alkane activity has been found to be linked to the reduction behaviour of the different undoped and doped NiMoO4 phases .