Process for removing SO.sub.2 from gases which contain it, with direct production of elemental sulfur

A process for removing sulfur dioxide from a gas which contains it, comprising the steps of:

• (a) reacting an SO.sub.2 -containing gas with an aqueous solution into which BaS has been supplied according to the reactions:
• 2BaS+2SO.sub.2 +2H.sub.2 O.fwdarw.2BaSO.sub.3 +2H.sub.2 S
• 2H.sub.2 S+SO.sub.2 .fwdarw.3S+2H.sub.2 O
• with a precipitate being thus formed which comprises BaSO.sub.3 and S, and filtering-off said precipitate,
• (b) dissolving elemental sulfur from said filtered-off precipitate, while leaving the BaSO.sub.3 unchanged, in a solid residue, and separting the resulting solution from said solid residue,
• (c) treating said solid residue from (b) with elemental carbon at a temperature of approximately 1100.degree. C., according to reactions including:
• 2BaSO.sub.3 +3C.fwdarw.2BaS+3CO.sub.2
• BaSO.sub.3 +3C.fwdarw.BaS+3CO
• and supplying the BaS solids into the absorption solution and recycling this resulting absorption solution to step (a);
• (d) distilling said resulting solution obtained in step (b) to recover elemental sulfur in pure form.