Vanadium pentoxide catalyst for oxidn of sulphur dioxide - on carrier made from bent onite, asbestos and kieselguhr

摘要

Catalyst for the oxidn. of SO2 to SO3 with O2, contg. V2O5, a carrier and a binder, is improved in that the carrier contains 5-20wt. % of bentonite, 5-30wt. % of asbestos and 50-90wt. % of kieselguhr. The V2O5-content is 5-10wt. % w.r.t. the total weight of the catalyst. The catalyst is produced by mixing together (pref. on a pelleting disc) V2O5, bentonite, asbestos and kieselguhr with addition of an alkali lye and a water-soluble alkali silicate, followed by H2SO4 and/or H3PO4 to form particles, which are subsequently hardened at 500-700 degrees C. The catalyst is used for SO2 oxidn. by the double contact method; it has very high thermostability necessary for high temps. (up to 650 degrees C) at high SO2 concn. (9-12 vol. %) occurring during the first stage of the process. The catalyst has good mechanical strength, resistance to abrasion and surface activity. The starting matls. are relatively inexpensive.