Determination of sultones

Sultones at 500p.p.m. or more may be determined by the following method [21]. At lower concentrations they may be determined by liquid chromatography or colorimetry. 

Extract the non-detergent organic matter from a 5 g sample. 

Evaporate the extract to dryness (caution flammable vapour) in a 100 ml round-bottomed flask. 

Sultones at concentrations from 10 to 500p.p.m. may be determined as follows [22]. 

Colour reagent dissolve 0.35 g methylene blue in 200 ml water in a 11 volumetric flask. Slowly and with continuous swirling add 6.5 ml concentrated sulphuric acid. Dilute to volume and mix. 

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