Sulphur dioxide removal from waste gas - using aq. sulphuric acid contg. manganese salt, oxygen and ionising radiation as activator

摘要

In the processing of waste gases contg. SO2 by contact with an aq. H2SO4 soln. in the presence of O2 or air and an inorg. Mn salt (I) as catalyst, giving H2SO4 soln. contg. SO2, the use of an activator or SO2 to give a SO2-free H2SO4 soln., removal of aq. H2SO4 soln. from the system in an amt. equiv. to the amt. of SO2 oxidised and recycling the rest of the aq. H2SO4 soln. to the contact process, (I) is MnSO4, Mn(C104)2, MnCl2, Mn(NO3)2 or Mn3(PO4)2 and is used in an amt. of 0.0003-0.03 wt.% (as Mn ion) and the SO2-contg. aq. H2SO4 soln. from the contact stage is subjected to the action of ionising radiation as activator. The catalyst and activator are selected so that a high degree of extn. of SO2 from the waste gas is ensured at a relatively high concn. of H2SO4 (up to 50%, cf. max. 40% when O3 is used for oxidn.). The need for cooling of the waste gas before processing is eliminated.