A comparative study of the catalytic properties for the oxidation of C₂-C₃ alkanes and olefins has been carried out over unpromoted and M-promoted NiO catalysts (Me = K, La, Ce, al, Zr, Sn, Nb). The catalysts have been characterized by several physico-chemical techniques (UV Raman, Visible Raman, FTIR of adsorbed CO and XPS). The characteristics of promoter elements are of paramount importance, since they are able to modify both the nature of the active nickel and the concentration of electrophilic O₂⁻/O⁻ oxygen species. Thus, a relatively high acidity and valence of the promoter oxide (with oxidation state higher than + 3) are necessary to achieve high selectivity to olefins during the oxidative dehydrogenation (ODH) of C₂–C₃ alkanes. In addition, an inverse correlation between the selectivity to the corresponding olefin and the concentration of electrophilic oxygen species has been observed, although the selectivity to propene during propane ODH is lower than the selectivity to ethylene achieved during ethane ODH. On the other hand, a very low influence of alkane conversion on the selectivity to the corresponding olefins is observed. This behaviour can be explained by considering that the reaction rate for olefin combustion is lower than the reaction rate for alkane oxidation. However, the comparative study of the oxidation of alkanes and olefins suggest that the differences observed between the ODH of propane and ethane are not related to the reactivity of olefins, but to the different number and reactivity of C–H bonds in both alkanes. A discussion on the importance of the concentration of active sites and the characteristics of the alkanes fed on the selectivity to olefin during the alkane ODH is also presented.

已经在未助催化和M助催化的NiO催化剂（Me = K，La，Ce，al，Zr，Sn，Nb）上对C ₂ -C ₃烷烃和烯烃的氧化催化性能进行了比较研究。催化剂已通过几种物理化学技术（UV拉曼，可见拉曼，吸附的FTIR和XPS）进行了表征。启动子的元件的特性是极为重要的，因为它们能够改变活性镍的性质和亲电的O浓度₂ ^- / O ^-氧气种类。因此，在C ₂ -C ₃的氧化脱氢（ODH）过程中，要获得对烯烃的高选择性，必须使用相对较高的酸度和价的促进剂氧化物（氧化态高于+ 3）。烷烃。此外，尽管在丙烷ODH过程中对丙烯的选择性低于在乙烷ODH过程中对乙烯的选择性，但已观察到对相应烯烃的选择性与亲电子氧物种浓度之间的反相关。另一方面，观察到烷烃转化率对相应的烯烃的选择性的影响非常低。可以通过考虑用于烯烃燃烧的反应速率低于用于烷烃氧化的反应速率来解释该行为。但是，对烷烃和烯烃氧化的比较研究表明，丙烷和乙烷的ODH之间观察到的差异与烯烃的反应性无关，但与两种烷烃中C–H键的数量和反应性无关。