is used as a catalyst. Catalysts are used to increase the rate of reaction.
Here, is used as a catalyst to reduce the higher temperature requirements and it increases the rate of reaction as well.
Vanadium pentoxide is the catalyst used in the converter stage of the contact process.
Vanadium Pentoxide acts like a catalyst to speed up the conversion of SO2 to SO3 as it is a very slow process. The equation of the reaction is given below.
Note: Vanadium pentoxide is not reacting in this reaction but is acting as a platform for the reaction to occur at a rapid pace.