Hydrogen sulfide from process

One of the principal aspects of refinery gas cleanup is the removal of acid gas constituents, ie, carbon dioxide, CO2, and hydrogen sulfide, H2S. Treatment of natural gas to remove the acid gas constituents is most often accompHshed by contacting the natural gas with an alkaline solution. The most commonly used treating solutions are aqueous solutions of the ethanolamines or alkah carbonates. There are several hydrogen sulfide removal processes (29), most of which are followed by a Claus plant that produces elemental sulfur from the hydrogen sulfide. 

Commercial-scale processes have been developed for the production of hydrogen sulfide from heavy fuel oils and sulfur as well as from methane, water vapor, and sulfur. The latter process can be carried out in two steps reaction of methane with sulfur to form carbon disulfide and hydrogen sulfide followed by hydrolysis of carbon disulfide (116). 

Conversion Processes. Most of the adsorption and absorption processes remove hydrogen sulfide from sour gas streams thus producing both a sweetened product stream and an enriched hydrogen sulfide stream. In addition to the hydrogen sulfide, this latter stream can contain other co-absorbed species, potentially including carbon dioxide, hydrocarbons, and other sulfur compounds. Conversion processes treat the hydrogen sulfide stream to recover the sulfur as a salable product. 

NKK s Bio-SR process is another iron-based redox process which instead of chelates, uses Thiobacillusferroidans )2iQ. - 2i to regenerate the solution (9). This process absorbs hydrogen sulfide from a gas stream into a ferric sulfate solution. The solution reacts with the hydrogen sulfide to produce elemental sulfur and ferrous sulfate. The sulfur is separated via mechanical means, such as filtering. The solution is regenerated to the active ferric form by the bacteria. 

Potassium Permanganate. Probably the most widely used process for removing traces of hydrogen sulfide from carbon dioxide is to scmb the gas with an aqueous solution saturated with potassium permanganate [7722-64-7]. Sodium carbonate is added to the solution as buffer. The reaction is as foUows ... 

Citric acid is used to chelate vanadium catalyst in a process for removing hydrogen sulfide from natural and refinery gas and forming elemental sulfur, a valuable product (133). 

J Consider the coke-oven gas COG sweetening process shown in Fig. 3.22. The basic objective of COG sweetening is the removal of acidic impurities, primarily hydrogen sulfide, from COG (a mixture of H2, CH4, CO, N2, NH3, CO2, and H2S). Hydrogen sulfide m undesirable impurity, because it is corrosive and contributes to SO2 emission when the G... 

Sulfur is a reactive, nonmetallic element naturally found in nature in a free or combined state. Large deposits of elemental sulfur are found in various parts of the world, with some of the largest being along the coastal plains of Louisiana. In its combined form, sulfur is naturally present in sulfide ores of metals such as iron, zinc, copper, and lead. It is also a constituent of natural gas and refinery gas streams in the form of hydrogen sulfide. Different processes have been developed for obtaining sulfur and sulfuric acid from these three sources. 

The above reaction can be driven in the forward direchon by continuously removing hydrogen sulfide from the system. This is accomplished in the sulfide reduction process by incorporating lime, which acts as a scavenger for hydrogen sulfide in accordance with the reaction... 

ASR Sulfoxide [Alberta Sulfur Research] A process for removing residual sulfur dioxide and hydrogen sulfide from the tail gases from the Claus process by wet scrubbing with a solution containing an organic sulfoxide. Elemental sulfur is produced. It had not been piloted in 1983. 

ATS [Ammonium thiosulfate] A process for removing residual sulfur dioxide from Claus tail gas by absorption in aqueous ammonia to produce ammonium sulfite and bisulfite. Addition of hydrogen sulfide from the Claus unit produces saleable ammonium thiosulfate. Developed by the Pritchard Corporation and first operated by the Colorado Interstate Gas Company at Table Rock, WY. 

Axorb A process for removing carbon dioxide and hydrogen sulfide from gases by scrubbing with an aqueous solution of potassium carbonate containing proprietary additives. 

Bio-SR A process for removing hydrogen sulfide from gas streams. Developed by NKK Industries, Japan. It uses a solution of unchelated iron, regenerated microbiologically. 

Carl Still (2) A process for removing hydrogen sulfide from coke oven gas by scrubbing with aqueous ammonia, itself derived from coke oven gas. Developed in the 1970s by Firma Carl Still, Germany. Operated at the ARMCO steel mill at Middleton, OH. See also Diamox, Still. 

Cataban A process for removing small amounts of hydrogen sulfide from industrial gas streams by oxidation, in aqueous solution, to elemental sulfur. The oxidant is the ferric ion,... 

CATACARB [Catalyzed removal of carbon dioxide] A process for removing carbon dioxide and hydrogen sulfide from gas streams by absorption in hot potassium carbonate solution containing a proprietary catalyst. Developed and licensed by Eickmeyer and Associates, KS, based on work at the U.S. Bureau of Mines in the 1950s. More than a hundred plants were operating in 1997. See also Benfield, Carsol, Hi-pure, Giammarco-Vetrocoke. 

Claus A process for removing hydrogen sulfide from gas streams by the catalyzed reaction with sulfur dioxide, producing elementary sulfur. The process has two stages in the first, one third of the hydrogen sulfide is oxidized with air to produce sulfur dioxide in the second, this sulfur dioxide stream is blended with the remainder of the hydrogen sulfide stream and passed over an iron oxide catalyst at approximately 300°C. The resulting sulfur vapor is condensed to liquid sulfur. 

Collin A process for removing hydrogen sulfide from coal gas by absorption in aqueous ammonia. The hydrogen sulfide was regenerated and used for making sulfuric acid. Invented by F. Collin in 1940 and operated in England and Europe in the 1950s. 

Double Loop A process for removing hydrogen sulfide from natural gas. In the first loop an organic solvent absorbs the hydrogen sulfide from the gas. In the second, an aqueous solution of an iron chelate converts this to elemental sulfur. Developed by Radian International... 

Folkins A process for making carbon disulfide from methane and sulfur at elevated temperature and pressure. A complex separation system removes the hydrogen sulfide from the products so that this sulfur can be re-used. The process can be operated catalytically or non-catalytically. Developed in 1948 by H. 0. Folkins and others at the Pure Oil Company, Chicago. 

Invented in 1930 by R. G. Bottoms at the Girdler Corporation, Louisville, KY. In 1950 it was the most commonly used process for removing hydrogen sulfide from refinery and natural... 

Iron Sponge Also called Dry box. An obsolete process for removing hydrogen sulfide from gas streams by reaction with iron oxide monohydrate. The ferric sulfide that is formed is periodically re-oxidized to regenerate ferric oxide and elemental sulfur. When this process becomes inefficient because of pore-blockage, the sulfur is either oxidized to sulfur dioxide for conversion to sulfuric acid, or is extracted with carbon disulfide. 

Konox A process for removing hydrogen sulfide from industrial gases by absorption in aqueous sodium ferrate (Na2Fe04) solution. The ferrate is reduced to ferrite (NaFe02) and the sulfide is oxidized to elemental sulfur. The main reactions are ... 

Manchester A variation on the Ferrox process for removing hydrogen sulfide from industrial gases in which several absorbers are used, and delay stages permit completion of the reaction with the iron oxide absorbent. Developed by the Manchester Corporation Gas Department in the 1940s and installed in several British gasworks. 

Purisol A process for removing hydrogen sulfide from gases by selective absorption in N-methyl-2-pyrrolidone (NMP). Developed and licensed by Lurgi, particularly for desulfurizing waste gases from IGCC plants. Seven units were in operation or under construction in 1996. 

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