The method of determining lower alkylamines followed

 

(57) Abstract:

Use: analytical chemistry control content lower alkylamines followed in the environment. The inventive method comprises preparing an aqueous solution of the sample, the processing of aqueous extraction-alleluya mixture, in which a mixture of 0.5 to about 4. % solution of dichloroacetylene in an inert organic solvent, in the presence of a solution of a carbonate of an alkali metal concentration of 0.5 to 2 mol/L. table 2.

The invention relates to analytical chemistry and can be used to control volatile alkylamines followed in the environment.

There is a method of quantitative determination of volatile amines by transferring them from solution into the gas phase in the form of free bases in a sealed vessel when interacting with an excess of alkali, followed by gazohromatografirovaniem gas phase [1] .

A drawback of the analysis of amines in the form of reason is the low accuracy of determination due to adsorption losses of reactive amines on the contacting surfaces of the vessel and device for vapor dosing, evaporator and sorbent XP is by gas chromatography determination of primary and secondary amines in the form of pentafluorobenzene derivatives [2] , which is the conversion of amines into their derivatives with simultaneous extraction of the obtained amino derivatives by treatment with an aqueous solution of the sample for 10 min extraction-alleluya mixture followed by gas chromatography of the extract amino derivatives.

The disadvantage of this method is the low performance analysis.

The aim of the invention is to increase productivity analysis.

The aim is achieved in that in the method of determining lower alkylamines followed by preparing an aqueous solution of amino, processing the obtained aqueous extraction-alleluya mixture in the presence of a carbonate of an alkali metal and gazohromatografirovaniem obtained extract amino derivatives, the extraction reaction of acylation is carried out with the use of a solution of a carbonate of an alkali metal concentration of 0.5-2 mol/l, and as extraction-alleluya use a mixture solution of dichloroacetylene in an inert organic solvent in the following ratio of components, about. % : dichloroacetylene 0.5 to 4; organic solvent - rest.

Use as extracts is the rate of component, and the proposed content of the carbonate of the alkali metal in the aqueous phase provides significant productivity analysis due to the higher reactivity of the proposed mixture under conditions for the analytical determination of micro-quantities of the investigated substances.

When the content of the carbonate of the alkali metal in the aqueous phase below 0.5 mol/l is sharply reduced the output of one of the lower alkylamines followed - methylamine, which leads to a decrease in the sensitivity analysis (table. 1), the upper bound of the range (2 mol/l) determined from the properties of solubility of Na2CO3in the water. The proposed ratio of components extraction-alleluya mixture is also associated with conditions to ensure the maximum output of the analyzed compounds. When the content of dichloroacetylene in an organic solvent is less than 0.5. % or more than about 4. % decreases the output of most of the analyzed compounds (table. 2).

P R I m e R 1. To 1 ml of a mixture of hydrochloride amines 0.5% sulfuric acid containing 4.0 µg of methylamine (MA), 0.8 µg dimethylamine (DMA), 4 g of ethylamine (EA) and 1.0 μg of diethylamine (deja), add 1 ml of a solution of Na2CO3a concentration of 1 mol/l and 1 ml of freshly prepared allerease, the organic layer is separated and 2 µl of toluene extract is injected into the chromatograph evaporator Color-100". Chromatographic analysis is performed on a glass column (0.3 x 300 cm), filled with sorbent Chromatin-super with 15% PEG-20 M (0.2 to 0.25 mm) at a temperature of column 170aboutC. the results of the analysis of the content of the analyzed components amounted to 4.0 µg MA (100% ), of 0.79 ág DMA (99% ), and 3.8 µg EA (95% ), of 0.96 ág deja (96% ).

P R I m m e R 2. To 1 ml of a mixture of hydrochloride amines 0.5% sulfuric acid containing 0.4 µg MA, 0.08 µg DMA, 0.4 µ g EA and 0.1 µg deja add 1 ml of 1 M Na2CO3and 1 ml of freshly prepared alleluya mixture (0.5% solution dichloroacetylene in toluene). Further processing and chromatographic analysis carried out analogously to example 1. The results of the analysis are found to be 0.4 µg MA (100% ), 0,079 µg DMA (99% ), of 0.42 µg EA (105% ) and 0,091 µg deja(91% ). (56) 1. USSR author's certificate N 1051422, CL G 01 N 30/00, 1983.

2. Ripley B. D. et al. Gas chromatographic determination of Primary and Secundary Amines as Pentafloorbenzamide Derivates. - J. Assoc. off. Anal. Chem. 1982, v. 65, N 2, p. 1066-1072.

The METHOD of DETERMINING LOWER alkylamines followed by preparing an aqueous solution of the sample, processing aqueous extraction-alleluya mixture in the presence of carbonate Sch the purpose of improving performance, the concentration of the solution of the carbonate of an alkali metal chosen from 0.5 to 2 mol/l, and as extraction-alleluya use a mixture solution of dichloroacetylene in an inert organic solvent in the following ratio of components, about. % :

Dichloroacetylene 0,5 - 4

Organic solvent Else

 

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