Prepared at the 17th JECFA (1973), published in FNP 4 (1978) and in FNP l of the aqueous solution obtained in the Test for stearyl alcohol, add 1 ml of calcium chloride TS and 3 drops of bromothymol blue TS and slightly acidify with dilute hydrochloric acid TS. Add sodium hydroxide TS until the colour changes to a clear blue, then boil the solution for 3 min, agitating it gently during the heating period: a white crystalline precipitate appears which is insoluble in sodium hydroxide TS but is soluble in acetic acid TS.
To 10 ml of the aqueous solution obtained in the Test for stearyl alcohol, add 1 ml of mercuric sulfate TS. Heat the mixture to boiling, and add a fewdrops of potassium permanganate TS: a white precipitate of the acetone dicarboxylic acid salt of mercury is formed.
PURITY
Other acids and alcohols Acids other than citric and alcohols other than those present in commercial stearyl alcohol must not be present