CATALYST FOR PREPARING PHTHALIC ANHYDRIDE Russian patent published in 1995 - IPC

FIELD: petrochemistry. SUBSTANCE: the catalyst comprises a catalytically active material, preferably in an amount of 3 to 20 g per 100 g of a heat resistant inorganic carrier. The catalytically active material comprises 1-20 wt parts of vanadium pentoxide V₂O₅, 80-99 wt parts of titanium dioxide TiO₂ of anatase type having a specific surface area of 10-60 cm²/g, and also 0.05-1.2 wt parts of potassium, cesium, rubidium, thallium as oxide, and further 0.05-2 wt parts of silver oxide per 100 wt parts of said components. The catalytically active material may preferably comprise 0-1 wt part of niobium pentoxide and 0-5 wt parts of antimony trioxide, the content of these components being not equal to zero. In a layer of catalytically active material applied to the heat resistant carrier the total volume of fine pores with a diameter of 0.15-0.45 mcm amount to 50% or more of the total volume of fine pores with a diameter of 10 mcm or less. EFFECT: improved properties of the catalyst. 4 cl, 5 tbl