| 摘要 |
FIELD: chemistry. ^ SUBSTANCE: method of detecting nicotinic acid in aqueous solution involves preparation of an aqueous salt solution of nicotinic acid by dissolving it in a saturated solution of a salting-out agent, its extraction and analysis of the equilibrium aqueous phase. The method is distinguished by that, the salting-out agent used in preparing the aqueous salt solution of nicotinic acid is a saturated solution of ammonium sulphate. The aqueous salt solution of nicotinic acid is prepared with pH 6.5, for which a weighed amount of nicotinic acid of mass 2 mg, weighed on an analytical balance, is put into a 100 ml graduated flask which is then filled with a saturated solution of ammonium sulphate, or sodium sulphite, or ammonium sulphite. Nicotinic acid is extracted with an aqueous polymer solution of poly-N-vinyl-pyrrolidone with concentration of 10 to 5 mol/l with volume ratio of the polymer solution to aqueous salt solution equal to 1:5. ^ EFFECT: increased extraction ratio of nicotinic acid from the aqueous solution. ^ 1 cl, 1 ex, 1 tbl |
