SU1726381A1 - Procedure for purification of copper sulfate - Google Patents

Abstract

The invention relates to methods for purifying copper sulphate from impurities and can be used in the chemical industry in the production of copper sulphate and water reactive qualifications and in non-ferrous metallurgy in the production of technical copper sulfate with a high degree of iron impurity. The aim of the invention is to reduce copper sulphate losses and reduce production waste while maintaining a high degree of purification. The goal is achieved by the fact that in the proposed method, which includes the processing of copper sulfate with hydrogen peroxide followed by the introduction of the complexing agent. crystallization and separation of the product; nitrilotrimethylphosphonic acid (NTF) is used as a complexing agent followed by the addition of activated carbon in a weight ratio of NTF: activated carbon 1: (1t2) and separation of the precipitate, and the complexing process is carried out at a pH of 1.5-2.0 . 1 hp f.ly, .1 tab. (L

Description

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The invention relates to the purification of copper sulphate from iron impurities and can be used in the chemical industry in the production of copper sulphate of water and reactive qualifications in non-ferrous metallurgy in the production of copper sulfate with a high degree of purity of iron impurities.

A technical solution is known to purify copper sulphate from ferrous iron impurities by oxidizing it to trivalent hydrogen peroxide followed by treatment with sodium fluoride complexing agent at 80 ° C, resulting in the conversion of ferric iron to soluble sodium hexafluoroferrate (III) sodium complex.

Although the known purification method provides a high quality product, it has significant drawbacks associated with the accumulation of impurities of iron, as well as sodium and fluorine in the mother liquor. According to this method, during the crystallization of copper sulfate, 97-98% of the iron impurity remains in the mother liquor. The accumulation of iron in the mother solution

create in a 380 l stock solution containing 0.043 g / l of iron impurity at 80 ° C. In the resulting solution with a density of 1.36 g / cm3 and pH 2, 0.5 kg of hydrogen peroxide is introduced, kept for 0.5 h with continuous stirring and heating, and then 7.0 liters of 5% is introduced. nitrilotrimethylphosphonic acid solution. Maintain the solution under stirring and heating for 15 minutes, after which 0.35 kg of activated carbon is introduced and stirring is continued for 1 hour. The solution is filtered from the precipitate of nitrilotrimethyl iron phosphate with activated carbon. 7.8 kg of sulfuric acid are introduced into the filtered purified solution of copper sulfate, cooled to 20-22 ° C. The cooled suspension is fed to a centrifuge, where copper sulfate crystals are pressed. Pressed copper sulfate crystals are dried. The yield of crystals is 265 kg. The mother liquor containing 4 mg / l of iron is recycled to the stage of preparing the initial solution, after having been neutralized.

The following examples were carried out analogously to example 2. The following parameters varied: the pH of the process, the amount of activated carbon introduced.

The data are given in the table.

From the above examples it can be seen that the goal is achieved in the case of processing a solution of copper sulfate with nitrilotrimethylphosphonic acid at a pH of 1.5-2.0, followed by the introduction of activated carbon at a mass ratio of

NTF: activated carbon 1: (1-2) (examples 2 and 3).

In the case of reducing the pH of the solution to 1.0 (Example 4), increasing the pH of the solution is greater than 2.0 (Example 5), as well as with the introduction of activated carbon in an amount less than proposed or in the absence of coal in the process (Examples 6.8 ) - product quality indicators are deteriorating. In the maintenance of activated carbon in large quantities is impractical (example 7).

Thus, the proposed method allows to reduce copper sulphate losses and reduce the amount of production wastes while maintaining a high degree of purification, which ensures the creation of a continuous process.

Claims (2)

Invention Formula 1. A method for purifying copper sulphate from iron impurities, including treating a solution with hydrogen peroxide, introducing a complexing agent, crystallizing the product and drying it, revealing that, in order to reduce the loss of the target product and reduce production waste while maintaining a high degree of purification, - complexing agent using nitrilotrimethylphosphonic acid at pH 1.5-2.0 before the introduction of activated charcoal is activated charcoal and the precipitate is separated. 2. The method according to claim 1, wherein the complexing agent and activated carbon are introduced in a mass ratio of 1: (1-2), respectively. 200 180 0, 43 0.35 0, 43 0.35 1: 11: 1 1, 75 2.0 434.0 180 0.34 0.34 1: 1 1.5 28 180 0.35 0.3-5 1: 1 1.0 27 99.4 39.5 E9,599.0  , 0002 0.0002 0.0002 0.002 , 001 0.001 0.0010.001 180 0.35 0.35 1: 1 2.5 13 98.0 0,008 0.001 0,000 $ 0,0005 0,0005 0,0005 0,0005 0,0030 0,0010 0,0250,0050,001 0,0005 0,0005 0,0005 0,0005 0,0005 0.002 0.002-0.0020.002 0,040,030,050,050,05 180 0.35 0.175 1: 0.5 , 0 9 9.5 , 005 , 001 , 0005 , 001 , 0005 , 002 180 0.35 0.975 1: 2.5 1.75 22 99.5 0.0002 0.001 0.0005 0.001 180. 0.35 Do not enter. 2.0 24 99.0 0.006 0.001 0.0005 0,007 200tZOO 0.0005 0.0005 0.002 200-300 GOST 99.59E, 0 0,0020,004 0,0010,004 0,00050,0005 0,0010,005 0,00050,001 0,002Non Lim. 0.05 0.05 0.05 0.1