Chloro-Oleum

It has been generally observed that for chlorosulfonation, excess chlorosulfonic acid is generally used to obtain better yields. HCl gas is evolved during the first phase of the reaction, which needs to be scrubbed. It can then be recycled as dilute HCl into the CS A plant. However, many of the consumers of CS A are far away from the CS A manufacturing plants. In view of this, in-situ conversion of HCl gas back to CSA 

Chloro-oleum is manufactured by absorption of SO3 in chlorosulfonic acid with intermediate cooling between the absorption towers. The chloro-oleum is maiketed in various grades depending on the specific requirement by the consumer. The most popular strengths are 20-25% free SO3 and 15-20% free SO3. 

Advantages HCl is evolved wMch can be recycled to CSA Plant Reduced CSA consumption Reduced effluent generation 

Disadvantages See Effluent treatment required below Higher cooling capacity required 

Safety in use Easy to control Temperatrrre can rise qrrickly during reactions, and hence, more careftrl control required 

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Absorption of HCl in chloro-oleum in a polishing tower at very low tranperature to produce high strength CSA. 

Absorption of liquid sulfur trioxide in chloro-oleum to produce high strength chloro-oleum where the latent heat of evaporation of sulfur trioxide is used to control the temperature. 

High level of CSA in the chloro-oleum circulation pump tank. 

Action of HSO3CI on 2-substituted thiazoles affords the 5-chlorosulfonyl derivatives (337, 338). Addition of 6-phenylthiazolo[2,3-e]tetra2ole to oleum opens the tetrazole ring to form 2-azido-4-phenyI-thiazolyl-5-sulfonic acid, isolated as its salt (339). 5-Chloro-sulphonyl derivative is obtained similarly by action of HSO,Cl. 

Anthraquinone can be sulfonated, nitrated, or halogenated. Sulfonation is of the greatest technical importance because the sulfonic acid group can be readily replaced by an amino or chloro group. Sulfonation with 20—25% oleum at a temperature of 130—135°C produces predominandy anthraquinone-2-sulfonic acid [84-48-0]. By the use of a stronger oleum, disulfonic acids are produced. The second sulfonic acid substituent never enters the same ring a mixture of 2,6- and 2,7-disulfonic acids is formed (Wayne-Armstrong rule). In order to sulfonate in the 1-, 1,5-, or 1,8-positions, mercury or one of its salts must be used as a catalyst. 

Dichlorobenzyl chloride (l,2-dichloro-4-chloromethylbenzene) containing some 2,3-dichlorobenzyl chloride is produced by the chloromethylation of o-dichlorobenzene ia oleum solution (73). Chlorination of 2-chloro-6-nitrotoluene at 160—185°C gives a mixture of 2,6-disubstituted benzal chloride and 2,6-dichlorobenzyl chloride (74). 

Costs. Sulfur is cheaper as a starting material from which to raise S03 than liquid-stabilized S03, 65% oleum, 20% oleum, sulfuric acid, and chloro-... 

DTA shows that the reaction mixture from sulfonation of the nitro compound in 20% oleum, containing 35 wt% of 2-chloro-5-nitrobenzenesulfonic acid, exhibits 2 exothermic stages at 100 and 220° C, respectively, the latter being violently rapid. The adiabatic reaction mixture, initially at 89° attained 285°C with boiling after 17 h. At 180° the induction period was about 20 min [1], Sulfonation of 4-chloronitrobenzene with 65% oleum at 46°C led to a runaway decomposition... 

Chloro-5-nitrobenzene sulfonic acid is synthesized by addition of p-chloro-nitrobenzene as a melt to 20% Oleum (20% S03 in H2S04) at 100 °C [1], This is added over 20 minutes to Oleum heated at 50 °C. The temperature then rises to 120-125 °C due to the heat of reaction. The conversion is achieved by maintaining this temperature during several hours with 2 bar of steam. 

By the nitration of l-chloro-3,4-dinitrobenzene with nitric acid in the presence of 40% oleum, at a temperature of 140-150°C a picryl chloride isomer, 1-chloro-2,4,5-trinitrobenzene, is formed. 

Condensation of benzaldehyde with ethylbenzylaniline, sulfonation of the resulting leuco base with oleum, and oxidation of the leuco sulfonic acid with lead peroxide, produces light green SF (yellowish). The corresponding dye from o-chloro-benzaidehyde is erioviridine B. Both dyes have poor light fastness but are still widely usM because of their color strength. 

The commercial significance of SO3 for the preparation of sulfuric acid has already been mentioned, and this is the most important aspect of its industrial chemistry. However, substantial amounts of pure SO3 are prepared commercially for use in the manufacture of, for example, chloro- and fluorosulfonic acids, thionyl chloride, and as a sulfonating agent. Pure, hquid SO3 is obtained industrially by distillation from oleum. 

To a stirred solution of 4 -chloro-2-nitrodiphenylamine (6.78 g, 0.027 mol) in coned HjSO (20 mL) maintained at 20 °C by external cooling, was added dropwise 28 % oleum (25 mL). After 5 min, the mixture was slowly poured into a vigorously stirred solution of NaHCOj (150 g) in H O (2.5 L) and EtOH (300 mL). A yellow precipitate separated and the aqueous suspension was extracted with CH Cl (2.5 L). The extract was dried (Na SO ) and evaporated under reduced pressure to give a brown solid yield 4.05 g (64%). 

Methylaminoanthraquinone has been prepared from 1-chloro-, 1-bromo-, and 1-nitroanthraquinone by treatment with alcoholic methylamine under pressure from 1-methoxy- and 1-phenoxyanthraquinone with methylamine in pyridine solution at 150° from potassium anthraquinone-1-sulfonate with aqueous methylamine at 150-160° from 1-aminoanthraquinone by treatment with formaldehyde, or methyl alcohol in sulfuric acid or oleum and by hydrolysis of />-toluenesulfonyl-methylaminoanthraquinone with sulfuric acid. ... 

Treatment of (1) with oleum and nitric acids gives 5-nitro-[l] (6) with yields from 70 to 90%, depending on reaction temperature.5 A side product of this reaction is the [l]-5,6-dione (7), whose colorless iron(II) complex was of little interest at the time of its discovery. A versatile precursor to many other phenanthrolines, (7) is readily prepared by treatment of (1) with sulfuric and nitric acids in the presence of bromide.38-40 Through a dioxime intermediate, 5,6-diamino-[l] (8) is obtained.41 5-Amino-[l] (9) may be prepared directly from (6) with Sn-HCl reduction.39 Alternatively, amino-[l] may be formed by conversion of the corresponding chloro-[l] with ammonia.42... 

ALLILE (CLORURO di) (Italian) (107-05-1) Forms explosive mixture with air (flash point -20°F/-29°C). Violent polymerization and explosion may occur from elevated temperatures, light, acid catalysts, ferric chloride, aluminum chloride, Lewis acids, or Ziegler catalysts, finely divided metals. Violent reaction with oxidizers, alkyl aluminum chlorides. Incompatible with strong acids, oleum, amines, aluminum chloride, boron trifluoride, chloro-sulfonic acid, ethylene diamine, ethyleneimine, ferric chloride, sodium hydroxide. Slow decomposition with moisture. Attacks some coatings, plastics, and rubber. Corrosive to steel. Flow or agitation of substance may generate electrostatic charges due to low conductivity. 

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