From sulfur trioxide

Economic Aspects. Merchant sulfur dioxide is produced by eight North American manufacturers the total was about 410,000 metric tons in 1994 (310,000 in the United States, 90,000 in Canada). The largest producers in the United States are Rhc ne-Poulenc (from sulfur trioxide reduction by sulfur) and Hoechst Celanese. There is also a larger captive production. Growth of merchant sulfur dioxide is projected at 2—3%/yr. The mid-1995 price was 0.25/kg. 

Methyl polyfluoro-1-cyclobutenyl ethers react with sulfur trioxide to form fluoride and polyfluorocyclobutenones, but coproducts are their fluorosulfonyloxy derivatives resulting from sulfur trioxide insertion [5] (equation 5) The nonsul-fonyloxylated polyfluorocyclopentenones are favored when starting with methyl polyfluoro-1-cyclopentenyl ethers (equation 6). Ring insertion of sulfur tnoxide occurs during the reaction of 1-methoxytnfluorocyclopropene (equation 7)... 

Sulfuric acid and other strong inorganic acids, occupational exposures to mists and vapours from Sulfur trioxide... 

R. Steudel, Sulfuric acid from sulfur trioxide and water—a surprisingly complex reaction. Angew. Chem. Int. Ed. Engl. 34, 1313-1315 (1995). 

Diaryl-1,2,3,5-oxathiadiazines (277 from sulfur trioxide and aryl isocyanates) with (3-diketones yield pyrimidines (278). s-Triazine reacts with RCH2CN to give 4-aminopyrimidines (279 see Section 3.2.1.6.1 for a similar reaction), and with electron-rich alkenes and alkynes to yield pyrimidines such as (280) from EtC = CMe (Section 3.2.1.10.2). 

One of the few substances found to behave as an acid ui sulfuric acid is disulfuric (pyrosuifuric) acid, it is formed from sulfur trioxide and sulfuric acid ... 

Venturi concentrator The to be concentrated sulfuric acid is injected into the radiation scrubber and there brought into contact with a dry gas stream, which takes up and thereby removes the water vapor. The heat of evaporation is either supplied directly via hot gases (furnace gas) or indirectly by heating the acid to be concentrated (e.g. with tail gases from a double contact plant) or by heat exchange with hot sulfuric acid from sulfur trioxide absorption. In this preconcentration process waste heat can be utilized at low temperatures. The venturi concentrator is in particular employed when large quantities of dilute sulfuric acid or sulfuric acid strongly contaminated with solids has to be preconcentrated. 

A few examples have been described of Diels-Alder-like reactions with imides formally derived from sulfur trioxide.58 N-Sulfonylimides are quite reactive in a [2 + 2] fashion with alkenes, but their ability to generally act as dienophiles is yet to be established. Sulfonylimines do react with highly oxygenated dienes to give adducts after hydrolysis [Eq. (35)]. 

Chlorosulfonyl isocyanate (146, abbreviated as CSI) is a highly reactive isocyanate. It is a colorless, rather stable oil of bp 107-108 °C/760mm Hg, first prepared by Graf in 1956 from sulfur trioxide and cyanogen chloride67. 

V. Sulfur Imides Derived from Sulfur Trioxide.182... 

The synthesis of deuterium chloride (CP ) requires the preparation of completely deuterated sulfuric acid. This material is prepared from sulfur trioxide and 99 % deuterium... 

Explain how the sulfite ion (S03 ) differs from sulfur trioxide (SO3), shown in Figure 19.10. 

The formation of dibasic acids through the addition of water to both sulfur trioxide and platinic chloride becomes, from the above considerations, a similar phenomenon. According to the older view, the formation of sulfuric acid from sulfur trioxide and water is due to the opening up of one of the double bonds between the sulfur and one of the oxygen atoms, and the addition of the water as hydrogen and hydroxyl to this opened up group. 

Hermann, C. V. 1941. Heat of Formation of Oleums from Sulfur Trioxide and Water, Industrial... 

A Chinese paper discusses the problems involved in the manufacture of chlorosulfonic acid from sulfur trioxide and hydrogen chloride in sulfuric acid plants. These include the optimum raw gas composition (SOsiHCl molar ratio... 

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