SU1305582A1 - Method of determining anthraquinone - Google Patents

Abstract

The invention relates to the field of analytical chemistry, in particular to the quantitative determination of anthraquinone (AH) in industrial and waste waters, and allows to increase the sensitivity of the method. Determination of AH is carried out by treatment of the analyzed H2S04 sample in the presence of a catalyst, a 9-12% aqueous solution of boric acid. The resulting colored compound is extracted with chloroform and the extract is photometrized. This method increases the sensitivity of the analysis by 3-10 times with an error of i5%, and the impurities of aniline, sodium sulfide, etc., do not interfere with the determination. 3 tab.

Description

t. 1305582

This invention relates to analytical chemistry, and specifically to methods for determining anthraquinone in industrial and wastewater.

The purpose of the invention is to increase the sensitivity of the method.

Example. Analyze samples of water containing anthraquinone, mg / l: 0.0; 0.5; 1.0; 5.0; 10.0. To 5 ml of the analyzed sample of water are added 2 ml of concentrated sulfuric acid and 3 ml of a 10% boric acid solution. The contents were boiled in a water bath for 20 minutes. After cooling, e10

the concentration of the reagent is sulfuric acid. The use of sulfuric acid without a catalyst as a reagent does not ensure the progress of stage II reaction. And the formation of the final colored product - 1,4-dioxanthraquinone.

Thus, the optimal ratios for analysis are volume ratios — sample to be analyzed, concentrated sulfuric acid, 10% boric acid, equal to 5: 2: 3.

In the analysis, concentrated sulfuric acid is used; 5 ml of chloroform and a mixture of 1.83 with a fraction of sulfuric acid are vigorously shaken for a lot of 93.6-95.6.

10 min. Then, the chloroform layer of the spruce – 10% boric acid solution is fed into a test tube and the optical density of the obtained colored solution is measured on a spectrophotometer at a wavelength of 510 nm and thick;

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10 g of HjBOj is dissolved in 100 ml of distilled water, followed by heating the solution to boiling point. After cooling, a 10% boric acid solution is used in the method for determining anthraquinone.

1 cm layer

In tab. Table 1 shows the results of the determination of anthraquinone; Table 2 shows the results of the determination of anthraquinone at various concentrations of boric acid; 3 - the results of experiments with the addition of various volumes of 10% boric acid.

From tab. 2 that when the concentration of boric acid is 9-12%, the sensitivity of the method is 3 mg / l, and at a concentration of 10% it increases to 1 mg / l.

From tab. 3 that the optimum amount of catalyst is 3 ml, since under these conditions the reaction is carried out to the final stage - the formation of a colored product. At smaller volumes of the used catalyst, the second step of the reaction — hydrolysis of 1,4-disulfoanthraquinone — goes to the stage of formation of an unstained intermediate reaction product, 1,4-dioxydioxy dioxanthraquinone.

The use of a catalyst in volumes of more than 3 ml disrupts the flow of stage I of the reaction — the formation of 1,4-disulfonantraquinone through the use of

the concentration of the reagent is sulfuric acid. The use of sulfuric acid without a catalyst as a reagent does not ensure the progress of stage II reaction. And the formation of the final colored product - 1,4-dioxanthraquinone.

Thus, the optimal ratios for analysis are volume ratios — sample to be analyzed, concentrated sulfuric acid, 10% boric acid, equal to 5: 2: 3.

In the analysis, concentrated sulfuric acid with a density of 1.83 and a fraction of sulfuric acid of 93.6-95.6 is used.

10% boric acid solution

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10 g of HjBOj is dissolved in 100 ml of distilled water, followed by heating the solution to boiling point. After cooling, a 10% boric acid solution is used in the anthraquinone determination method.

As can be seen from the table. 1, the proposed method allows the quantitative determination of anthraquinone in wastewater at the level of existing hygienic standards (1 mg / l) and increases the sensitivity of the method by 3-10 times with an error of 15%. Aniline, sodium sulfide, and other substances produced by anthraquinone in sewage do not interfere with the determination.

Claims (1)

Invention Formula The method of determining anthraquinone, which includes treating the sample being analyzed with sulfuric acid in the presence of a catalyst, followed by optical analysis of the obtained colored compound, characterized in that, in order to increase the sensitivity of the method, a 9-12% aqueous solution of boric acid is used, the resulting colored compound extracted with chloroform, and the analysis is carried out by photometry of the extract. Table 1 table 2 Prod. kg table. 2 13055828 Continuation of table 2 Concentration, mg / l given definable (average of five definitions) 20 without boric acid 5.0 10.0 20.0 0.0 0.5 1.0 3.0 5.0 10.0 20.0 0.0 0.5 1.0 3.0 5.0 10.0 20.0 0.0 0.5 1.0 3.0 5.0 10.0 20.0 5.70 10.50 20.62 N / def 10.70 20.95 N / Opr 10.83 21, 35 N / Opr Definition error,% i12.3 ± 4.8 + 3.0 16.5 41.5 ± 8.7 + 6.3 II 1305582 12 Table 3 The volume of boric acid, ml Concentration, mg / l given without a catalyst 5.0 10.0 20.0 0.0 0.5 1.0 3.0 5.0, 10.0 20.0 0.0 0.5 1.0 3.0 5.0 10.0 20.0 Editor A. Kozoriz Compiled by S.Hovanska Tehred L. Serdyukova Order 1422/41 Circulation 777 Subscription VNIIPI USSR State Committee on matters of inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab ,,; d. 4/5 Production and printing company, Uzhgorod, Projecto st., 4 Continued table. 3 Definition error,% definable (average of five definitions) ± 5.4 h 5.7 2.2 + 3.0 Proof-reader I.Erdeyi