IMPROVEMENT OF PROPERTIES OF CATALYST FOR INDUSTRIAL-PRODUCTION OF ACROLEIN FROM PROPYLENE

The catalytic gas-phase oxidation of propylene on a multicomponent Mo- Co-Fe-Bi-K-0 catalyst gives up to 85% yield of acrolein and acrylic ac id along with undesirable side products - formaldehyde and acetaldehyd e. Effects of four factors have now been studied with the aim of suppr essing of formation of the by-products viz. the effect of potassium co ntent in the catalyst, that of final annealing temperature of the cata lyst, and those of addition of other components (tungsten, nickel). It has been found that a change in potassium content in catalyst affects distinctly its activity and also selectivity for products of total ox idation of propylene but does not practically affect the yields of for maldehyde and acetaldehyde. The yields of the said side products decre ased with increasing annealing temperature, however, with concomitant considerable decrease in the catalyst activity. Whereas a partial subs titution of molybdenum atoms in the catalyst by tungsten atoms is acco mpanied by an increase in production of formaldehyde and acetaldehyde, some catalysts with nickel gave acrolein as the only aldehyde.