CATALYTIC PROPERTIES OF ALKALI-PROMOTED VANADIUM CATALYSTS FOR OXIDATION OF SULFUR-DIOXIDE

Alkali-promoted catalysts M-2' S2O7-M-2 '' S2O-rV(2)O(5)/SiO2 (M' = Cs , Rb, and K; M '' = K, Na, and Li) of various compositions for synthes is of sulfuric acid were studied in the range of low temperatures and conversions. Light alkali metals M '' were shown to be able to increas e or decrease the catalytic activity depending on the nature of the ma in promoter M'. In the context of molecular concepts of the structure of vanadium catalysts and the mechanism of their catalytic activity, p lausible reasons for the positive and negative influence of alkali pro moters on the rate of oxidation of SO2 to SO3 were discussed.