Treating processes hydrogen

Chevron s WWT (wastewater treatment) process treats refinery sour water for reuse, producing ammonia and hydrogen sulfide [7783-06-04] as by-products (100). Degassed sour water is fed to the first of two strippers. Here hydrogen sulfide is stripped overhead while water and ammonia flow out the column bottoms. The bottoms from the first stripper is fed to the second stripper which produces ammonia as the overhead product. The gaseous ammonia is next treated for hydrogen sulfide and water removal, compressed, and further purified. Ammonia recovery options include anhydrous Hquid ammonia, aqueous Hquid ammonia, and ammonia vapor for incineration. There are more than 20 reported units in operation, the aimual production of ammonia from this process is about 200,000 t. 

Other gas-treating processes involving sulfolane are (/) hydrogen selenide removal from gasification of coal, shale, or tar sands (qv) (108) (2) olefin removal from alkanes (109) (J) nitrogen, helium, and argon removal from natural gas (110) (4) atmospheric CO2 removal in nuclear submarines (5) ammonia and H2S removal from waste streams (6) H2S, HCl, N2O, and CO2 removal from various streams (111—120) and (7) H2S and SO2 removal from... 

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. 

Another variation of the Selectox process can be used with the Beavon process in tail gas treating. The hydrogenated Claus tail gas stream is sent to a Selectox reactor. Overall recoveries of up to 98.5% are possible. Use of Beavon/Selectox, however, typically costs more than use of Superclaus. 

When a ketone 1 is treated with hydrogen peroxyde or a peracid, a formal insertion of oxygen can take place to yield a carboxylic ester 2. This process is called the Baeyer-Villiger oxidation ... 

It is recognized, that the overall process consists of the catalysis of reaction 1, an intermediate step being the reduction of water. Reaction 4 can be treated as hydrogen evolution on a compact silver electrode at negative potential. Silver has a small overpotential for evolution Of the two steps of which reaction 4 is composed... 

MILOX [Milieu oxidative] A wood-pulping and bleaching process. Wood chips are treated with hydrogen peroxide and formic acid in a three-stage process. Developed by the Finnish Pulp and Paper Research Institute (KCL) and Kemira. Piloted at Oulu, Finland in 1991. 

The mother liquor obtained from the crystallized hydrazine sulfate contains a small amount of hydrazine. If 200 g. of copper sulfate are dissolved in water and added to 10 1. of the filtrates from the above processes, a light-blue crystalline precipitate of the double salt of copper sulfate and hydrazine sulfate will be formed after ten hours. This salt, when suspended in ten times its weight of distilled water and treated with hydrogen sulfide,... 

Since the Claus process by itself removes only about 90% of the hydrogen sulfide in the gas stream, the Beavon process (Speight, 1993, p. 268), SCOT (Shell Claus Off-Gas Treating) process (Speight, 1993, p. 316 Hydrocarbon Processing,... 

Downstream of the compressor is a series of fractionators (generally the tallest towers in an ethylene plant) which separate the methane and hydrogen, the ethylene, the ethane, and the propane and heavier. All are heavy metallurgy to handle the pressures and insulated to maintain the low temperatures. There s also an acetylene hydrogenator or converter in there. Trace (very small) amounts of acetylene in ethylene can really clobber some of the ethylene derivative processes, particularly polyethylene manufacture. So the stream is treated with hydrogen over a catalyst to convert the little acetylene present into ethylene. 

In the author s laboratories the polymerization of aldehydes, ketones, and alcohols by liquid hydrogen fluoride has been repeatedly noted. Acetaldehyde polymerizes and acetone forms polymeric substances on standing for a period of time in solution in hydrogen fluoride. If the solution is separated shortly after mixing, the acetone may be recovered. The same is true of tertiary alcohols. The peculiar action of tertiary chlorides (Simons et al., 35) probably results at least in part from polymerization. The products obtained most likely come from destruction of the polymers in the process of distillation. Benzaldehyde forms a shellac like resin when treated with hydrogen fluoride. A rather interesting polymerization reaction occurs upon treating aralkyl ketones with... 

Hydro I re citing—A treating process for the removal of sulfur and nitrogen from feedstocks by replacement with hydrogen. 

Hydrogenation is a chemical process where liquid oils are converted to solid fats. In this process, hydrogen is added to oils in the presence of a catalyst. Inedible oils or less useful oils are converted to edible, hard fats by this process. For example, cotton oil is treated with hydrogen at about 500°C in the presence of a catalyst. The resultant hard fat is used for cooking. 

Gulfining a catalytic hydrogen treating process for cracked and straight-run distillates and fuel oils, to reduce sulfur content improve carbon residue, color, and general stability and effect a slight increase in gravity. 

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