Abstract: Sulfur is produced by contacting, in a catalytic selective oxidation zone, a feed gas comprising an acid gas stream containing hydrogen sulfide in admixture with about 70 to 130 percent of the stoichiometric amount of oxygen required for conversion of hydrogen sulfide to sulfur and a recycle gas which is a portion of the gas resulting from condensing sulfur from the effluent of the catalytic selective oxidation zone with a catalyst selectively capable of oxidizing hydrogen sulfide to sulfur dioxide substantially without formation of sulfur trioxide to form a gas stream comprising hydrogen sulfide, sulfur dioxide and sulfur at a temperature between the kindling temperature of the catalyst and about 850.degree. F. Formed sulfur is condensed from the effluent gas stream and a portion of the substantially sulfur-free effluent returned as recycle gas.

Abstract: Sulfur is produced by contacting, in a catalytic selective oxidation zone, a feed gas comprising an acid gas stream containing from about 1 to 100 percent by volume in admixture with about 70 to 130 percent of the stoichiometric amount of oxygen required for conversion of hydrogen sulfide to sulfur and a recycle gas which is a portion of the gas resulting from condensing sulfur from the effluent of the catalytic selective oxidation zone, with a catalyst selectively capable of oxidizing hydrogen sulfide to sulfur dioxide substantially without formation of sulfur trioxide to form a gas stream comprising hydrogen sulfide, sulfur dioxide and sulfur at a temperature between the kindling temperature of the catalyst and about 850.degree. F. Formed sulfur is condensed from the effluent gas stream and a portion of the substantially sulfur-free effluent returned as recycle gas.

Abstract: Liquified hydrocarbon gases containing at least carbonyl sulfide as an impurity are purified by intimately mixing the liquified hydrocarbon gas with an aqueous absorbent for hydrogen sulfide in a hydrolysis zone maintained at a temperature and a pressure sufficient to maintain the liquified hydrocarbon gas in the liquid state and hydrolyze the carbonyl sulfide to hydrogen sulfide and carbon dioxide. The liquified hydrocarbon gas containing at least a portion of the formed carbonyl sulfide and carbon dioxide is separated from the liquid absorbent and passed to an absorption zone where it is contacted with a liquid hydrogen sulfide absorbent where at least the formed hydrogen sulfide is separated from the liquified petroleum gas. A stage of absorption of at least hydrogen sulfide may proceed mixing of the liquified hydrocarbon gas with the absorbent in the hydrolysis reaction zone.

Abstract: A liquid or solid hydrocarbon is partially oxidized in the presence of steam and oxygen in a high temperature reducing flame zone to which at least sulfur dioxide is added to consume generated hydrogen and carbon monoxide formed in a second flame zone to form hydrogen sulfide as necessary for a Claus reaction. Elemental sulfur is thermally formed. The gas stream is rapidly cooled to prevent further reactions, then further cooled to condense sulfur. The resultant gas stream is passed to one or more Claus conversion zones where hydrogen sulfide and sulfur dioxide react to form sulfur.

Abstract: A hydrocarbon is partially oxidized in the presence of steam and oxygen in a high temperature reducing flame zone to which sulfur is added in excess of the quantity of hydrogen and carbon monoxide formed to generate a second flame zone. The gas stream is rapidly cooled to prevent further reactions, then further cooled to condense sulfur to the extent of providing unreacted hydrogen and carbon monoxide in a molar excess over the residual sulfur present in the gas stream. The resultant gas stream is passed to a catalytic conversion zone where residual sulfur and carbonyl sulfide are converted to hydrogen sulfide. A formed gas stream free of sulfur and sulfur dioxide may be cooled to below the dew point of water to remove water prior to use.

Abstract: A reducing gas stream containing hydrogen, carbon monoxide and water, as steam, is passed through a molten sulfur to vaporize sulfur. The gas stream containing the vaporized sulfur is passed through a catalytic conversion zone where at a controlled temperature of from about 500.degree. to about 800.degree. F sulfur is converted to hydrogen sulfide. The introduced steam optionally coupled with a water quench following hydrogenation of sulfur serves to suppress carbonyl sulfide and carbon disulfide formation.

Abstract: Apparatus for heating and mixing industrial tail gases with a reducing gas by burning a mixture of fuel, air, and steam in a combustion chamber having a small outlet opening at the end of the chamber. A jacket surrounds the combustion chamber. The industrial gases are circulated around the combustion chamber inside the jacket, heat being transferred from the combustion chamber to the industrial gas. It is then mixed with the combustion products from the outlet of the combustion chamber to form a high temperature mixture of an industrial gas and a reducing gas for subsequent processing.

Abstract: To permit the processing of hydrogen sulfide-fixed nitrogen compound feed streams, e.g. H.sub.2 S--NH.sub.3 mixtures without causing plugging problems usually encountered in a Claus sulfur plant due to the formation of solid nitrogen sulfur salts, a first hydrogen sulfide feed containing substantial quantities of fixed nitrogen compounds, a portion of a second hydrogen sulfide feed essentially free of fixed nitrogen compounds and air are combined in a first thermal reaction zone where the amount of oxygen present is sufficient to achieve a high flame temperature for essentially complete conversion of the fixed nitrogen compounds to inert nitrogen, but insufficient to consume all of the hydrogen sulfide present. The effluent of the first reaction zone is combined with the balance of the second hydrogen sulfide feed in a second thermal reaction zone where hydrogen sulfide and sulfur dioxide react to form sulfur.

Abstract: An improvement to a Claus sulfur plant uses heat generated in the partial combustion of hydrogen sulfide to produce high pressure steam which is utilized before each catalytic conversion stage to heat the reactive gas stream to a temperature consonant with that required for the catalytic conversion of the sulfur dioxide and hydrogen sulfide in the gas stream to water and sulfur.

Abstract: The energy requirements of a process for the solvent extraction of hydrocarbons from residua are reduced by nearly 50%, and capital requirements reduced substantially by evaporating solvent from extracted hydrocarbons in two or more pressure stages, the first stage evaporation occurring at a pressure sufficiently high to permit condensation of the solvent at a temperature sufficient to be combined with the solvent feed to the extractor at the required extraction temperature.

Abstract: To permit the processing of hydrogen sulfide-fixed nitrogen compound feed streams, e.g. H.sub.2 S-NH.sub.3 mixtures without causing plugging problems usually encountered in a Claus sulfur plant due to the formation of solid nitrogen sulfur salts, a first hydrogen sulfide feed containing substantial quantities of fixed nitrogen compounds, a portion of a second hydrogen sulfide feed essentially free of fixed nitrogen compounds and air are combined in a first thermal reaction zone where the amount of oxygen present is sufficient to achieve a high flame temperature for essentially complete conversion of the fixed nitrogen compounds to inert nitrogen, but insufficient to consume all of the hydrogen sulfide present. The effluent of the first reaction zone is combined with the balance of the second hydrogen sulfide feed in a second thermal reaction zone where hydrogen sulfide and sulfur dioxide react to form sulfur.