Hydroxylamine monosulfonate

D. Dimethylglyoxime.—The crude biacetyl monoxime, remaining after distilling to 90° and containing about 5 moles of biacetyl monoxime, is added to the sodium hydroxylamine monosulfonate solution (which has been filtered to remove any sediment) and which is contained in a 15-I. flask. It is heated to 70° and allowed to remain warm (with occasional stirring) for several hours (Note 9). The dimethylglyoxime separates in crystals which can be filtered from the solution as soon as it has become cold (Note 10). The crystals are washed with cold water until free of sulfate. The yield of compound melting at 238-240° is 540-575 g-... 

C. Sodium Hydroxylamine Monosulfonate.—In a 12-I. crock are mixed 5 kg. of shaved ice (Note 6) and 569 g. of sodium nitrite (594 g. of the technical 95 per cent quality). Into this is stirred a suspension of sodium bisulfite containing noo g. of available sulfur dioxide (about 1775 g. of technical bisulfite) in 750 cc. of water. Then, beneath the surface of the solution is added, with constant stirring, 150 cc. of glacial acetic acid... 

The biacetyl monoxime turns brown rapidly after preparation and it must not be allowed to stand before adding it to the hydroxylamine monosulfonate in the preparation of dimethylglyoxime if this final product is to be obtained in a colorless condition. 

Hydrolysis of Hydroxylamine Disulfonate (HAPS). HADS hydrolyzes to give hydroxylamine monosulfonate (HAMS) and sulfates ... 

Sulfonation of Hydroxylamine Monosulfonate (HAMS). According to Seel et al. (14), the reactions between HAMS and bisulfite are branched ones (Eqs. 17 and 18), producing about 70% amine-disulfonate (ADS) and 30% sulfamate (SAM) in the temperature range 25-60°C and ionic strength range 1.0-1.2 M, with reaction times ranging up to 12 hr at a pH of 7 ... 

Production of hyponitrous acid and sulfates from the reaction of hydroxylamine monosulfonate with nitrous acid. 

A classical method of preparing a standard solution of sodium hydroxylamine disulfonate is given here. Some disagreement exists in the literature as to the exact nature of this reagent. Sometimes it is referred to as sodium hydroxylamine monosulfonate [3,4]. 

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