| abstract |
Novel catalyst for the prepn. of unsatd. carbonyl cpds. by the gas phase oxidn. of olefins, contains Mo in the oxide form and opt. other Gp. 6B elements, together with >=1 element of Gp. 4A, 5A and 8B. The atomic ratio of the elements present is Mo 12; opt. Cr + W + U =6; Gp. 4A elements, i.e. Si, Ge, Sn, Pb 0.5-10; Gp. 5A elements i.e. P, As, Sb, Bi 0.1-10; Gp. 8B elements i.e. Fe, Co, Ni 0.1-10. There is also present a Mg cpd. or a cellulose deriv., or hexamethylene tetramine in a mol. ratio to Mo of 0.0005-2:12. The catalyst has high activity, improved mechanical props., porosity and low bulk density compared with known catalysts. It is partic. suitable for the selective oxidn. of propylene to acrolein and acrylic acid. |