Patent ID: 7341974

Claim:
Method for preparing an unsupported catalyst of formula (I) for partial oxidation of propylene, comprising the step of adding salts of metal components constituting the catalyst to an aqueous solution containing organic acid having 1 to 10 carbon atoms for preventing layer separation to obtain a catalyst suspension: Mo a Bi b Fe c X d Y e O f (I) wherein, X is at least one element selected from the group consisting of Co and Ni; Y is at least one element selected from the group consisting of K and Rb; and a, b, c, d, e and f represent the atomic ratio of each element, provided that when a is 12, then b is 0.5 to 2, c is 0.5 to 2, d is 3 to 8, e is 0.005 to 0.2 and f is the value corresponding to the oxidation state of each element.