Dry sepn. of acid gases including nitrogen mon:oxide - by reaction with calcium hydroxide wetted with dil. potassium permanganate or other oxidant

摘要

(Dry) sepn. of NOx, SO2, HCl and HF, esp. from sintering plants and power stations, is effected by contacting the gas with Ca(OH)2 wetted with dil, KMnO4 or similar reagents, e.g. H2O2, Na2S2O3, NaOCl etc., which react with NOx and lime and form a cpd. The end prod., which can be processed further, is sepd. in a (dry) filter. Pref. Ca(OH)2 is sprayed with dil. KMnO4 soln. before contact with the crude gas, when the MnO2 formed catalyses the oxidn. of NO to NO2, which is bound by the Ca(OH)2 as Ca(NO3)2. The process enables the sepn. of NO to proceed in parallel to the reaction of Ca(OH)2 with SO2 to CaSO3 and CaSO4. The prod. can be dumped or used as additive in the plaster or cement industry.