METHOD FOR PHOTOMETRIC DETERMINATION OF IRON (III) IN SOLUTIONS OF PURE SALTS IN PRESENCE OF SURFACE-ACTIVE SUBSTANCE Russian patent published in 2018 - IPC G01N31/22 G01N21/78 

FIELD: analytical chemistry.

SUBSTANCE: invention relates to the field of analytical chemistry, namely to the photometric method of analysis, and can be used to determine the content of iron (III) in solutions of pure salts containing iron (III) in a very low concentration. Method involves transferring iron (III) into a complex compound with an organic reagent – xylenol orange and a surfactant in a weakly acidic medium, adding distilled water to 10 ml volume with heating in a water bath at a temperature of 60–80 °C and subsequent photometry of the resulting solution after cooling, to build a calibration curve to 0.5 ml (0.8–2.0)⋅10^-3 M solution of iron (III) with a pH of 4.0–5.0, created by the introduction of 3.0 ml of acetate buffer solution, add 1.0 ml 1⋅10^-2 M solution of xylenol orange and 0.2 ml 4⋅10^-3 M solution of surfactant in the form of perfluorooctyl alcohol ethoxylate and distilled water up to 10 ml, at the same time, heating in a water bath is carried out for 10 minutes, and when photometric measurement a cuvette is used with a thickness of 0.5 cm.

EFFECT: increase in accuracy and reliability is achieved, as well as an acceleration of analysis.

1 cl, 9 dwg, 1 ex, 1 tbl