SU1658040A1 - Method of determination of nickel (ii) in ammonium sulfate solutions containing manganese ions - Google Patents

Abstract

This invention relates to analytical chemistry and can be used in non-ferrous and ferrous metallurgy, in particular in hydroelectrometallurgy of manganese. The purpose of the invention is to simplify and accelerate the determination of nickel (II) in ammonium sulphate solutions containing manganese ions. The color intensity of nickel ions is increased by adjusting the pH of the solution, then the solution is photometrical using a red filter of 625-700 nm and a cell of 50 mm. 2 tab.

Description

This invention relates to analytical chemistry and can be used in ferrous and nonferrous metallurgy, in particular in manganese hydroelectrometallurgy.

The purpose of the invention is to accelerate and simplify measurements.

The method is carried out as follows.

Adjust the pH of the test solution to 8 and photometrate the resulting solution relative to water in the range of 625-700 nm.

The essence of the method is that at pH 8 light green color of nickel ions becomes more intense blue-green color, while manganese ions are kept in solution in a dissolved state, since the pH of hydrate formation is not reached. A red light filter is introduced into the optical system of the photocolorimeter, which absorbs the blue-green rays of nickel ions, but remains transparent to the pink color of the manganese ions. This makes it possible not to limit the content of manganese in the analyzed solutions.

Example 1. Solution composition: 150 g / l ammonium sulphate, pH 8, red filter 625-700 nm, cuvette 5 cm, comparison solution - water. When the manganese concentration is from 0 to 40 g / l, the optical density is zero. This suggests that the red filter is transparent to pink manganese ions and, therefore, when analyzing solutions for nickel, the manganese content in the solution should not be limited.

PRI mme R 2. The composition of the solution: 35 g / l manganese, 150 g / l sulphate (L

with

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ate

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31658040

go ammonium, 5 g / l nickel / II /. The red light filter is 625-700 nm, the cuvette is 5 cm, the comparison solution is water.

Table 1

table 2

7.5 0.30 Light green,

transparent

7.7 0.30 Light green,

transparent

8.0 1.17 Blue-green, transparent

8.2 - Blue-green, unstable, becomes cloudy, manganese hydroxide is formed

From tab. Figure 1 shows that, at pH 8, the solution color is not intensified, at pH 8, along with the solution intensification, the solution becomes cloudy due to the formation of manganese hydroxide, and photo-colorimetration becomes impossible.

Example 3. The composition of the solution: 35 g / l of manganese, 150 g / l of ammonium sulphate and nickel (II), pH 8. Red filter 625-700 nm, kyu. Veta 5 cm; Comparative solution - water.

In tab. 2 shows examples of determination (II) in the presence of manganese. Optical density was measured on a FEC-M photoelectric colorimeter, and the nickel concentration was determined using a calibration curve compiled from standard solutions.

Claims (1)

Invention Formula The method for determining nickel (II) in ammonium sulphate solutions containing manganese ions, including preparing a sample of the test solution and photoning it, is due to the fact that, in order to simplify and speed up the determination, the pH of the test solution is adjusted to 8 and photometrized in the range 625-700 nm.