The disproportionation of propene has been investigated over catalysts prepared from molybdenum hexacarbonyl supported on silica, alumina, silica-alumina and magnesium oxide. The activity of these catalysts is found to depend markedly on the temperature at which the support is outgassed before the molybdenum hexacarbonyl is added and on the temperature of activation after addition of the hexacarbonyl. These variations in activity are discussed in terms of the sites on the supports which are available for interaction with the molybdenum hexacarbonyl, and the possible state of the molybdenum in active catalysts.
Smith, J., Howe, R. F., & Whan, D. A. (1974). The activity of supported molybdenum hexacarbonyl catalysts for the disproportionation of propene. Journal of Catalysis, 34(2), 191-195. https://doi.org/10.1016/0021-9517(74)90027-X