SORPTION-SPECTROPHOTOMETRIC METHOD OF DETERMINING LEAD (II) Russian patent published in 2014 - IPC G01N21/77 

FIELD: chemistry.

SUBSTANCE: metal is concentrated from a sample at a fixed pH value, for which an acetate buffer with pH 3.5-4.5 is added to the analysed solution, an indicator film is immersed in the obtained solution for 30-60 minutes and optical density is measured on a spectrophotometer at wavelength of 610 nm after removing said film from the solution. Concentration of lead is determined by a standard addition method or calibration curve method. The indicator film used is a transparent polymer substrate coated with a gelatine layer with thickness of less than 20 mcm, immobilised with aqueous solution of bromopyrogallol red.

EFFECT: high sensitivity and selectivity of determining lead, wider range of determined concentrations and enabling combination of separation, concentration and direct determination of lead.

3 cl, 4 dwg, 6 tbl