METHOD FOR PHOTOMETRICALLY DETERMINING IRON(II) IN SOLUTIONS OF PURE SALTS AND ARTIFICIAL MIXTURES Russian patent published in 2007 - IPC G01N31/22 G01N21/78 

FIELD: analytical methods.

SUBSTANCE: group of inventions relate to photometric determination of iron(II) in solutions of pure salts and artificial mixtures containing iron (II) in very low concentration. First embodiment of invention comprises transfer of iron(II) into complex compound with aluminon in low-acidic medium. To that end, to solution of iron(II) with pH 2.2-7.0 is added 100-120-fold amount of aluminon, 0.3-0.5 mL of surfactant solution (obtained by adding 0.9 mL laurin alcohol to 7 g gelatin and completing the mixture with water to 120 mL), and water to achieve the total of 10 mL, after which resulting mixture is heated for 8-10 min on water bath at 80-98°C. In the second embodiment, iron(II) is transferred into complex compound with aluminon in low-acidic medium: to solution of iron(II) with pH 3.0-5.2 is added 10-15-fold amount of aluminon, 0.2-0.4 mL of surfactant solution containing 2% of gelatin solution, and water to 10 mL of total volume, after which resulting mixture is heated for 1-3 min on water bath at 80-98°C.

EFFECT: increased sensitivity and selectivity of analysis.