Chloro sulphonic acid

Dissolve 1 0 g. of the compound in 5 ml. of dry chloroform in a dry test-tuhe, cool to 0°, and add dropwise 5g. (2-8 ml.) of redistilled chloro-sulphonic acid. When the evolution of hydrogen chloride subsides, allow the reaction mixture to stand at room temperature for 20 minutes. Pour the contents of the test-tube cautiously on to 25 g. of crushed ice contained in a small beaker. Separate the chloroform layer and wash it with a httle cold water. Add the chloroform layer, with stirring, to 10 ml. of concentrated ammonia solution. After 10 minutes, evaporate the chloroform on a water bath, cool the residue and treat it with 5 ml. of 10 per cent, sodium hydroxide solution the sulphonamide dissolves as the sodium derivative, RO.CgH4.SO,NHNa. Filter the solution to remove any insoluble matter (sulphone, etc.), acidify the filtrate with dilute hydrochloric acid, and cool in ice water. Collect the sulphonamide and recrystallise it from dilute alcohol. 

Method 1. Equip a 1 litre three-necked flask (or bolt-head flask) with a separatory funnel, a mechanical stirrer (Fig. II, 7, 10), a thermometer (with bulb within 2 cm. of the bottom) and an exit tube leading to a gas absorption device (Fig. II, 8, 1, c). Place 700 g. (400 ml.) of chloro-sulphonic acid in the flask and add slowly, with stirring, 156 g. (176 ml.) of pure benzene (1) maintain the temperature between 20° and 25° by immersing the flask in cold water, if necessary. After the addition is complete (about 2 5 hours), stir the mixture for 1 hour, and then pour it on to 1500 g. of crushed ice. Add 200 ml. of carbon tetrachloride, stir, and separate the oil as soon as possible (otherwise appreciable hydrolysis occurs) extract the aqueous layer with 100 ml. of carbon tetrachloride. Wash the combined extracts with dilute sodium carbonate solution, distil off most of the solvent under atmospheric pressure (2), and distil the residue under reduced pressure. Collect the benzenesulphonyl chloride at 118-120°/15 mm. it solidifies to a colourless sohd, m.p. 13-14°, when cooled in ice. The yield is 270 g. A small amount (10-20 g.) of diphen3 lsulphone, b.p. 225°/10 mm., m.p. 128°, remains in the flask. 

With fluoro- or chloro-sulphonic acids the P=N linkage is replacedby an S-N bond ... 

The following methods are available for the preparation of chloro-sulphonic acid (1) The substance can be obtained by the gradual action of moisture (e.g. atmospheric moisture) on sulphuryl chloride a similar reaction occurs with sulphuric acid and is more easily regulated ... 

Concentrated or fuming sulphuric acid also gives rise to chloro-sulphonic acid when treated with phosphorus pentachloride 2... 

Formation.—When sulphur dioxide is passed into ice-cold fuming nitric acid, crystals of nitrosulphonic. acid separate.1 The acid is also obtained when sulphuric acid is treated with excess of nitrogen peroxide.2 It is also formed by the interaction of sulphur dioxide and nitrogen peroxide both in the absence or presence of water,8 and by the addition in equimolecular proportion of liquid nitrogen tetroxide to chloro-sulphonic acid in the absence of moisture.4 Sulphuric acid acts on either nitrous anhydride or nitrosyl chloride with formation of nitrosulphonic acid, according to the equations ... 

With phosphorus pentachloride nitrosulphonic acid yields chloro-sulphonic acid and nitrosyl chloride 8... 

Toluene-o-sulphonyl-chloride,—100 gms. pure toluene are slowly run into 500 gms. of chloro-sulphonic acid cooled to 0° in a pot fitted with good mechanical agitation, the temperature during the addition being kept at 0°—5°. When all the toluene has been added stirring is continued for about 12 hours at the same temperature. The mass is then poured... 

All carotenoid sulphates have been prepared by partial synthesis from the corresponding carotenols by reaction with a sulphur trioxide/pyridine complex prepared from chloro-sulphonic acid and pyridine [8-10], followed by sodium salt formation by addition of NaOH or, for alkali-labile carotenoids, NaCl [11], Scheme 1. The presumed mechanism is that S-0... 

The major consumption of Chloro Sulphonic Acid is for the follcwing Detergents ... 

Refer to the figure below. In case of horizontal mounting of another foundation, complete suction and discharge piping with valves can be kept ready for immediate changeover if the pump breaks down. But this will need more floor space, sets of valves, electrical cables, etc. For these pumps, external dyke walls are required in order to contain any toxic/corrosive liquid that may leak out from the pump and acid/alkali resistant tiles are also necessary. Mechanical seals are required for toxic/inflammable/corrosive fluids (oleums, chloro-sulphonic acid) so as to prevent leakages... 

At present the world production of Saccharine is in the range of 6000-8000 tonnes/year. The world requires minimum of 100,000 tonnes of Chloro Sulphonic Acid for sulphonation of toluene, a series of batch reactors requiring chilling unit for better conversion of toluene orther isomer. It will also produce 150,000 tonnes of hydro chloric acid (commercial grade 30 %) the innovative process will avoid the above drawbacks in the current manufacture and thereby produce saccharine at much cheaper price. 

Description Chloro Sulphonic Acid is taken into agitated reactors having jacket for cooling with chilled brine. A large capacity chilling plant is required to maintain sub-zero reaction temperatures to produce toluene sulphonyl chloride with more of ortho isomer compared to para. 

The high pressure reactor is fed with hquid SO3, toluene and chloro sulphonic acid by metering pumps. The reaction takes place in two phases ... 

Currenlty in India saccharine is sold at Rs. 700 (USD 110) per kg. The cost of the production is very high in view of the fact that one has to use twice the quantity of chloro sulphonic acid to the tune of 16 kg/kg of saccharine cost of which is equivalent to Rs. 150 (USD 2.25) per kg. In addition there is a high cost of utihties specially the chilling plant and operators manhours since the current process is batchwise. 

In situ conversion of hydrochloric gas evolved during reaction into chloro sulphonic acid required in the reaction... 

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