Catalyst for oxidising sulphur di:oxide to tri:oxide - has silica support with specified pore dia. distribution impregnated with activator

摘要

Catalyst for oxidn. of SO2 to SO3 consists of a SiO2 support activated with V and alkali metal cpds. The support: has a pore vol. fraction of 10-30% pores with dia. up to 15nm, 25-60% pores with dia. 15-200 nm and 10-60% pores with a dia. of over 200nm. The catalyst is produced by mixing SiO2 of the specified pore dia. with enough liquid (water and/or H2SO4) to give a mouldable mixt., moulding, drying and calcining the moulding (at 450-650 deg.C), impregnating the calcined material with activators and drying. USE/ADVANTAGE - The catalyst has very good mechanical properties (hardness and attrition in both the fresh and aged state), high activity over a wide temp. range (ca. 380-420 deg.C) and very low pressure drop. The high activity at relatively low temp. makes it possible to reduce operating costs by using a lower temp. than usual and also reduces SO2 emissions at low temp.