Cooperation between MoO3 and other metal oxides in selective oxidation of isobutene to methacrolein

Article abstract of DOI:10.1016/0304-5102(90)85198-Q

A synergy is observed in the selective oxidation of isobutene to methacrolein when MoO₃ is mixed mechanically with other metal oxides, either simple (Sb, Bi, Te) or binary (Cu-Sb, Bi-P, Zn-Fe, Ni-Mo, Co-Mo, Fe-Mo and Cu-Mo). In most cases, the effect can be explained by a remote control mechanism, namely the control of active sites of MoO₃ through spillover oxygen emitted by the other phases. Roles of these admixed phases can be related to the ionicity of the bonds in their structure. The results strongly suggest that TeO₂ behaves as an intermediate oxide, either as a donor when mixed with a strong acceptor or an acceptor when mixed with a strong donor.