Abstract: In a reactor housing for conducting the catalytic oxidation of gaseous sulfur compounds, a plurality of empty tubes are arranged in an outer zone of the housing for having incoming gas to be reacted flow therethrough. Larger catalyst-filled tubes are arranged in an intermediate zone for having the gas flow therethrough after flowing through the empty tubes for performing the catalytic oxidation in the larger catalyst-filled tubes. An inner chamber includes an axial-flow pump arranged therein and is in communication with the outer and intermediate zones in such a way that a heat-transfer agent is caused to flow cross-currently into and out of the outer zone, intermediate zone and inner chamber for contacting the empty tubes and catalyst-filled tubes.

Abstract: A process is provided for the production of hydrogen and sulphur from a gas containing hydrogen sulphide. Such a process comprises passing the gas through a cracking zone at a temperature of from about 850.degree. C. to 1600.degree. C., cooling the cracked gas to a temperature of from about 110.degree. C. to 150.degree. C., and separating the condensed elemental sulphur. The uncracked hydrogen sulphide is separated and returned to the cracking zone; the remaining gas is withdrawn as hydrogen-rich gas.

Abstract: In a process for the catalytic oxidation of gaseous sulfur compounds to sulfur trioxide comprising passing said gaseous sulfur compounds through a plurality of serially connected catalytic stages at 400.degree.-580.degree. C., the improvement which comprises circulating a liquid heat exchange medium in indirect heat exchange relationship to the reaction gases in the catalytic stages and with a heat consumer and optionally a heat source at a rate and amount such that the liquid heat exchange medium absorbs substantially all the exothermic reaction heat and fluctuates no more than 5 centrigrade degrees, thereby controlling the temperature of said catalytic stages.

Abstract: Sulfur dioxide in sulfur dioxide-containing gases is thermally reduced at relatively moderate temperatures under reducing conditions provided by the incomplete combustion of hydrocarbon to produce elemental sulfur. Elemental sulfur can be recovered from the effluent gases from the thermal reduction and the effluent gases may be treated by conventional catalytic processes to recover additional elemental sulfur from the remaining sulfur values.

Abstract: Elemental sulfur is recovered from ammonium salts of sulfuric oxyacids (e.g. ammonium sulfate, ammonium hydrogen sulfite, and ammonium sulfite) by passing the salt (e.g. in aqueous solution) and a hydrogenous reducing agent (e.g. sewer gas or coal gas) through a reaction chamber maintained at 800.degree. to 1300.degree. C. so as to yield a product gas containing molecular nitrogen, steam, and vaporous sulfur, and then cooling the product gas to 125.degree. to 325.degree. C. so as to condense at least a portion of the sulfur, which is then recovered.