METHOD FOR SPECTROPHOTOMETRIC DETERMINATION OF FLUORIDE ION IN NATURAL OBJECTS AND WASTE WATERS Russian patent published in 2017 - IPC G01N21/17 G01J3/40 

FIELD: chemistry.

SUBSTANCE: to determine the fluoride ion a chromogenic complex zirkonine - zirconium is applied, that interacts with fluoride ion in a new analytic reaction: (C₁₅H₁₂N₂O₈S)₂Zr+3HF+H⁺=[ZrF₃]⁺+2C₁₅H₁₄N₂O₈S, whereby the test sample is added to zirkonine complex with Zr, the optical density of the resulting solution is measured at a wavelength of 610 nm with respect to the reference solution containing no fluoride ion, and fluoride ion concentration in the sample is determined using the calibration curve. The method provides sensitivity of 0.02 mg/dm³, increased selectivity in the presence of sulfate, phosphate, nitrate and chloride ions, Al (III), Fe (III), and takes less than 1 minute.

EFFECT: increased sensitivity of the method.

1 dwg, 8 tbl, 8 ex