SU1330139A1 - 3-sulfo-5-nitro-4ъ-diethylamino-2,2ъ-dioxybenzene as agent for photometric determination of gallium,indium,molybdenum and vanadium - Google Patents

Abstract

The invention relates to the field of azo dye chemistry, in particular to the novel compound Z-sulfo-5-nitro-4-diethylamine-2,2-dioxyazobenzene. which can be used as a reagent for the determination of gallium, indium, molybdenum and vanadium. The invention allows to increase the contrast of reaction j for gallium and indium at 10 nm, for vanadium at 15 nm, for molybdenum at 30 nm and increase the detection sensitivity for gallium from 0.01 to 0.005 µg / ml, for indium from 0.05 to 0.025 µg / ml, i.e. 2 times, for molybdenum from 0.1 to 0.025 µg / ml, i.e. 4 times, for vanadium from 0.05 to 0.01 µg / ml, i.e. 5 times. The use of 3-sulfo-5-nitro-4-diethylamino-2,2-dioxyazobenzene for photometric determination of gallium, indium, molybdenum and vanadium in aqueous solutions helps to determine trace concentrations of toxic metals in natural and waste waters below the level of maximum permissible concentrations in water bodies . 1 tab. Ш (Л со оо со со

Description

1 The invention relates to chemistry

1330139

connection, in particular to the new

ten

When the whole solution of the diazo salt is applied, the mixture is kept at room temperature for 1 hour, then heated to 60 ° C, 20 g of potassium chloride are brought into the hot solution and the solution is left overnight. The precipitation is filtered off, washed with alcohol and with a tub in a vacuum desiccator over caustic alkali.

Found,%: C 46, AO; H 4.15; N 13.40; S 7,8. S.BNZ S

Calculated,%: C 46.83; H 4.39; 15 N 13.65; S 7.5.

Example 2. 3-Sulfo-5-nitro-4-diethylamino-2,2-dioxyazobenzene as a reagent for the photometric determination of a range of metals.

siazo benzene (sulfonitrazo DAP) i-20 ™ inci, molybdenum, vanadium).

em the following characteristics: pK „Comparative Studies on

azo compound, 3-sulfo-5-nitro-4-diethyl-amino-2,2-dioxyazobenzene, which can be used as a reagent for the photometric determination of gallium, indium, molybdenum and vanadium

3-Sulfo-5-nitro-4-diethylamino-2,2-dioxiazobenzene (sulfonitrazo DAP) is obtained by reacting azo combining 2-amino-4-nitrophenol-6-sulfonic acid with 4-diethylamino-2-hydroxybenzene in a weakly acidic medium. with the subsequent allocation of the target product by salting out.

New organic reagent 3-sulfo-5-nitro-4-diethylamino-2,2-diocon

wavelength max. mr absorption of reagent A „„,

Mts ks

4.7; 11.5; little

460 nm at a pH of 2.5-4.0. Sulfonitrazo DAP is soluble in water, stable in aqueous solutions and readily reacts at pH 2.5–4.0 with a number of metals (gallium, indium, molybdenum, vanadium) to form highly soluble complex compounds, therefore it can be used in analytical chemistry. as an organic reagent for photometric determination of these metals in aqueous solutions.

Example 1. Preparation of 3-sulfo-5-nitro-4-diethylamino-252-dioxyazobenzene.

0.05 mol (15 g) of 2-amino-4-nitro-phenol-6-sulfonic acid is dissolved in 50 ml of water, acidified with concentrated hydrochloric acid to pH 3-4, another 10 ml of concentrated acid is poured, cooled to (in a bath with ice) and dropwise, with constant stirring, add 10 ml of 5 N. solution of nitrous sodium. Stirring is continued at 0-5 ° C for 1 h, then the solution is separated by filtration from a small amount of free amine precipitate

The resulting solution of the diazo compound is added dropwise with stirring to an aqueous solution of 0.05 mol (8.35 g) of 4-diethylamino-2-hydroxybenzene,

contrast and sensitivity of the determination of gallium, indium, molybdenum, vanadium using the proposed 25 dieneum (3-sulfo-5-nitro-4-di-ethylamino-2,2-dioxyazobenzene) and the known (3-sulfo-5 -nitro-2,2, 4-trioxyazobenzene), selected as a prototype.

30 Methods of determination. An aliquot of each of the metals studied separately, containing 10 µg, is placed in a 25 MP volumetric flask, and 3-5 ml of a 0.05 M solution of phthalate buffer, pH 3.5, 1 ml of a 0.05% solution are added H-sulfo-5-nitro-4-diethylamino-2,2-dioxyazobenzene. The resulting solution was made up to the mark with distilled water, stirred and heated on a water bath (boiling) for 15 minutes. After cooling, the optical density is measured on an SF-16 spectrophotometer relative to a similarly prepared

(for galli.

35

40

45

solution of idle experience

indie 540 nm, dl. vanadium

545 nm, for molybdenum 560 nm).

50

Data indicating an increase in the contrast and sensitivity of the determination of gallium, indium, molybdenum, and vanadium using a new organic reagent, 3-sulfo-5-nitro-4-diethylamino-2,2-dissolving, with the addition of minor oxyazobenzene ( sulfonitrazo DAF) of the amount of alcohol (15 ml of water + compared with the well-known, most 10 ml of ethyl alcohol). The reaction with the azo-similar compound 3-combination is carried out in the acidic medium of sulfo-5-nitro-2,2,4-trioxyazoben (initial pH 4-5). By okzolom presented in the table.

Comparative Studies

contrast and sensitivity of the determination of gallium, indium, molybdenum, vanadium using the proposed 5 dieneum (3-sulfo-5-nitro-4-di-ethylamino-2,2-dioxyazobenzene) and the known (3-sulfo-5 -nitro-2,2, 4-trioxyazobenzene), selected as a prototype.

0 Method of determination. An aliquot of each of the metals studied separately, containing 10 µg, is placed in a 25 MP volumetric flask, and 3-5 ml of a 0.05 M solution of phthalate buffer, pH 3.5, 1 ml of a 0.05% solution are added H-sulfo-5-nitro-4-diethylamino-2,2-dioxyazobenzene. The resulting solution was made up to the mark with distilled water, stirred and heated on a water bath (boiling) for 15 minutes. After cooling, the optical density is measured on an SF-16 spectrophotometer relative to a similarly prepared

(for galli.

five

0

five

solution of idle experience

indie 540 nm, dl. vanadium

545 nm, for molybdenum 560 nm).

oxyazobenzene (sulphonitrase compared with the well-known, very close in structure sulfo-5-nitro-2,2, 4-trioxia

ash presented in the table.

As follows from the table), the contrast of the reaction of gallium, indium, molybdenum, vanadium with the proposed organic reagent is higher than the nitroazo DAP higher than with the known reagent. The reaction contrast or the shift of the maximum absorption wave of the complex compound of the metal relative to the reagent solution (LL) for gallium and indium increased by 10 nm, for vanadium by 15 nm, for molybdenum by 30. nm.

The lower limit of detectable content for gallium increased from 0.01 to 0.005 µg / ml; for indie from 0.05 to 0.025 μg / ml, i.e. 2 times; for molybdenum from 0.1 to 0.025 µg / mp; those. 4 times; for vanadium from 0.05 to 0.01 µg / ml, i.e. 5 times.

Therefore, the proposed reagent 3-sulfo-5-nitro-4-diethylamino-2, 2-dioxyazobenzene in comparison with the known analogue on the structure of 3-sulfo-5-nitro-2,2, 4-trioxyazo-benzene in the photometric determination of metals provides an increase in reaction contrast for gallium, indium by 10 nm, for vanadium

VNIIPI Order 3539/26

Random polygons pr-tie, Uzhgorod, st. Project, 4

thirty

at 15 nm, for molybdenum at 30 nm and

increase in detection sensitivity for gallium and indium 2 times, for molybdenum 4 times, for vanadium 5 times.

The use of the proposed organic reagent for photometric determination of such metals as gallium, indium, molybdenum, vanadium in aqueous solutions allows determining the trace levels of toxic metals in natural and waste waters below the level of the maximum permissible concentrations in the water of water bodies.

40

45

Claims (1)

Invention Formula 3-Sulfo-5-nitro-4-diethylamino 2,2-dioxyazobenzene of the general formula Hojs he he 50) 2 N02 as a reagent for photometric determination of gallium, indium, 55 molybdenum and vanadium. Circulation 633 Subscription