Catalytic activity in the oxidative dehydrogenation of ethane over Ni and/or Co molybdate catalysts: Synthesis and characterization

Abstract

Ni and/or Co molybdate based catalysts were synthetized by co-precipitation for the oxidative dehydrogenation of ethane reaction. The catalysts were characterized by several techniques such TGA-DTA, HT-XRD, XRD, LRS, N 2 adsorption, XPS and TPR. The results showed that the addition of Ni or Co to MMoO 4 matrices (M=Ni or Co) led to a high dispersion of additives into the molybdenum matrix without the formation of a significant amount of other bulk metal oxides. Compared to the pure MMoO 4 , the modified molybdenum (Ni 0.5 Co 0.5 MoO 4 ) presents a higher thermal stability (up to 1000 °C). It has a lower BET surface area and higher reduction temperature compared to those of the NiMoO 4 sample. In the ODH of ethane, Ni 0.5 Co 0.5 MoO 4 shows a lower catalytic activity compared to that of MMoO 4 samples; however, the ethylene selectivity is enhanced (exceeding 90%). As a result, these series of catalysts show improved efficiency for ethylene production in the ethane ODH reaction.