SU951127A1 - Perflourvalerian acid determination method - Google Patents

Description

The analyzed water sample (25 ml is placed in a separating funnel, 50 ml of 10% aqueous solution HjSOij., Saturated with Nad (pH 3.5-4) are added, mixed thoroughly. Then 6 ml of a benzene solution saturated with diphenylcarbazone are poured. Shake for 5 minutes. Mixture is allowed to stand until complete separation of the benzene solution of diphenylcarbazone. The layer of benzene solution is drained into the tube. After 15-20 minutes, the optical density of the colored solution is measured on a spectrophotometer at a wavelength of 552 nm, the thickness of the absorbing layer 1 see poppy Absorption of the obtained colored compound corresponds to 552 nm. At concentrations ranging from 0.05 to 3 mg / l, there is a linear dependence of optical density on perfluorovaleric acid concentration. Minimum Concentration, mg / L, is determined by

0.12 0.11 0.13 0.10 0.09

0.57 0.55 0.50 0.48 0.60

1.08 1.10 1.00 0.95 1.15

1.58

1.5 1.60 1.50 avg

0.11

± 10%

± 8%

0.54

+ 6%

1.06

± 3%

The 1.54 concentration of perfluorovaleric acid, which can be determined, is 0.05 mg / l. Example. Analyze water samples containing perfluorvaleric acid 0.1: 0.5; 1.0; 1.5; 2.0 mg / l. For the analysis, 25 ml of the test water is taken, which is placed in a separating funnel, and 50 ml of a 10% aqueous solution of HijSO saturated with NaCl (pH 3.5–4.0.) Are added. Then, 6 ml of benzene solution saturated with diphenylcarbazone are added. The contents are shaken vigorously. After 15–20 minutes, a layer of benzene solution is poured into a test tube and the optical density of the colored solution is measured on a spectrophotometer at a wavelength of 552 nm and an absorbing layer thickness of 1 cm. The results of the performed analyzes are shown in the table. Error of determination},% of detected

Table continuation

Claims (2)

Claims of determination of perfluorovaleric acid by treating an analyte with a color reagent - benzene solution of diphenylcarbazone, separating the benzene layer with its subsequent photometric measurement, are soothed and so that, in order to increase the sensitivity of the method, color reagent treatment is carried out in the presence of of sodium chloride. Sources of information taken into account during the examination 1. E. Peregud, E. Gernet. Chemical analysis of industrial air. L-., Himi, 1970, p. 168. 2. Korenman I.M. Photometric analysis. Methods for the determination of organic compounds. M., Himi, 1975, p. 230 (prototype) ..