Abstract: An apparatus for recovering sulfur from gases containing hydrogen sulfide by the process described in German Auslegeschrift No. 1,941,703 is provided. The apparatus is, however, suitable for processing gas mixtures containing any concentration of hydrogen sulfide met with in industry and comprises a first reaction chamber for the reaction of liquid sulfur with oxygen, nozzles installed in said chamber to give as complete mixing and circulation of the constituents as possible, and a second reaction chamber for the subsequent mixing and reaction of the sulfur dioxide formed in the first reaction chamber with the hydrogen sulfide content of the gas mixture to be treated, containing hydrogen sulfide. The two reaction chambers are connected to one another by means of orifices so that the reactions of S.sub.2 with O.sub.2 and of SO.sub.2 with H.sub.2 S take place at separate spaces and successively.