SU1182349A1 - Method of determining 2-chloroethylphosphonic acid - Google Patents

Abstract

METHOD FOR DETERMINING 2-HLORETSH1FOSFONOVOY acid and its salts, characterized in that, in order to simplify the method, a drop of analyte is applied onto filter paper pre-soaked, followed by drying, a mixture containing a saturated solution of i-dimethylaminobenzaldehyde, 13.1% -ny sodium acetate solution, yttrium acetate solution containing, in May.%: yttrium acetate 3.0-4.0, hydrochloric acid 0.1 and the rest water and 1.3% solution of hydrazine sulfate, containing, in wt%: hydrazine sulfate 1.2-1.4; 2% caustic soda solution 0.05 and water the rest, in the following ratio of mixture components, wt.%: 13.1% sodium acetate solution 8-10 acetate solution (L yttry 3.6-10.3 С 13.1% solution of hydrazine sulfate 1.7-1.8 Saturated solution of p-dimethylaminobenzaldehyde Else

Description

The invention relates to analytical chemistry, in particular to the determination of 2-chloroethylphosphonic acid and its salts, plant growth regulators, used in agriculture in the form of aqueous solutions.

The aim of the invention is to simplify the method.

The method is carried out as follows.

Prepare the original solutions.

A. A saturated aqueous solution of p-dimethylaminobenzaldehyde (0.1%), 1.5 g of p-dimethylaminobenzaldehyde is dissolved in 1 liter of hot water, allowed to cool to

at a natural temperature and B. is filtered off. A 13.1% solution of sodium acetate. 13.6 g of sodium acetate are dissolved in water, hydrochloric acid is added to pH 5.5-6.0 and water to 100 ml.

B. Acetate buffer solutions. Proceed as per p. B, but adjusted to pH 6.0-6.5 (buffer No. 1) and to 4.5-5.5 (buffer No. 2).

G. A solution of yttrium acetate containing 9 mg / ml yttrium (0.9%). 3.4 g of yttrium acetate is dissolved in water, one drop of hydrochloric acid is added and the volume is made up to 100 ml with water.

D. 1.3% solution of hydrazine sulfate. 1.4 g. dissolved in 80 ml of water. Add 2% solution to pH 5.5-6.0 and water to about 100 ml.

To prepare indicator paper for determining 2-chloroethylphos, background acid and its salts, a strip of filter paper is drawn through a solution obtained by mixing 90-100 ml of solution A; 9-11 ml of solution B; 3.6-4.4 solution G and 1.9-2.1 ml of solution D.

The resulting indicator papers are dried; after drying, they turn a light yellow color.

When determining 2-chloroethylphosphonic acid in solutions for spraying plants and in wastewater, the indicator paper touches the test solution. It is colored orange-red. You can drop a drop of the test solution on the indicator paper.

If the pH of the test solution is between 4-6.5, as evidenced by a sample with a universal pH paper, proceed as indicated above. Otherwise, a drop of Buffer No. 1 is first added to a drop of the test solution, if the solution is more acidic, or a drop of Buffer No. 2, if the solution is more alkaline.

Openable minimum: 0.5 µg of 2-chlorinated lophosphonic acid or its salt in a micro droplet of 0.001 ml.

In tab. 1 shows the composition of the initial solutions.

In tab. Table 2 presents examples of formulations with minimum, maximum, and optimum weight ratios of ingredients. In the determination of 2-chloroethylphosphonic acid and its salts using the compositions listed in table. 2, almost identical results were obtained.

Table 1

Used p-dimethylaminobenzaldehyde aqueous solution

p-dime tilaminobe from guide, water

13.1% sodium acetate solution

Sodium Acetate, Three-Water

0.1 99.9

13.1 86.9

Continuation of tal1l

Continuation of table 2

Claims (1)

METHOD FOR DETERMINING 2-CHLOROETHYL PHOSPHONIC ACID AND ITS SALTS, characterized in that, in order to simplify the method, a drop of the analyte is applied to a filter paper, pre-impregnated with subsequent drying, with a mixture containing a saturated solution of i-dimethylaminobenzaldehyde, 13.1% - sodium acetate solution, yttrium acetate solution containing, wt.%: yttrium acetate 3.0-4.0, hydrochloric acid 0.1 and the rest water and 1.3% hydrazinium sulfate solution, containing, wt.%: hydrazinium sulfate 1.2-1.4; 2% sodium hydroxide solution 0.05 and water the rest, with the following ratio of the components of the mixture, wt.%: 13.1% sodium acetate solution yttrium acetate solution 13.1% hydrazinium sulfate solution saturated solution η- dimethylaminobenzaldehyde 8-10 3.6-10.3 1.7- 1.8 Rest SU _g „1182349 1 .1 182349