摘要 |
(Meth)acrylonitrile is prepd. by reacting propylene or isobutylene with air and/or O2 and NH3 in a fluidised bed at 350-520 degrees C and 0.1-10 atm. in the presence of a provided catalyst consisting of a mixt. of the oxides of Fe, Bi, the Mo and P on silicic acid support. The catalyst is prepd. by (a) forming a powdered catalyst component consisting of bismuth phophomolybdate-silicic acid, (b) impregnating the catalyst component with an aq. soln. of an Fe salt, pref. ferric nitrate, the soln. being used in a vol. equal to 1-2.5 times the vol. of the pores of the catalyst component, (c) gradually drying the wet catalyst at 120-250 degrees C with simultaneous decompsn. of the Fe salt to Fe oxide, and (d) roasting the dry catalyst at 600-700 degrees C. The catalyst gives high yields and degrees of conversion, and is resistant to abrasion in the fluidised bed. The catalyst has a long life. |