RU2500629C2 - Method of destructing anion of 1-hydroxyethane-1,1-diphosphoric acid in production wastes - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to methods of deactivation of toxic wastes of galvanic and radio-electronic production and can be applied for deactivation of waste solutions of galvanic and chemical metal coatings, which contain anion of 1-hydroxyethane-1,1-diphosphonic acid, as well as for neutralisation of waste solutions of etching of printed circuit boards, which contain ammonium perpxodisulphate. Method consists in mutual neutralisation of two liquid wastes of production as a result of oxidation of anion of 1-hydroxyethane-1,1-diphosphonic acid by peroxodisulphate to nontoxic chemical substances.

EFFECT: method makes it possible to convert more than 99% of anion of 1-hydroxyethan-1,1-diphosphonic acid into orthophosphate, reduce material costs for neutralisation of toxic wastes of production of galvanic coatings and printed circuit boards and extend arsenal of methods for utilisation of waste solutions of etching of printed circuit boards, which contain ammonium perpxodisulphate.

11 cl, 4 dwg, 4 ex

Description

The invention relates to methods for the neutralization of toxic waste from galvanic and electronic production and can be used to neutralize spent solutions for the deposition of galvanic and chemical coatings with metals that contain the anion of 1-hydroxyethane-1,1-diphosphonic acid as a ligand for binding the metal to the complex, and can also used to neutralize spent etching solutions of printed circuit boards containing ammonium peroxodisulfate.

Complex electrolytes and solutions containing the anion of 1-hydroxyethane-1,1-diphosphonic acid CH ₃ C (OH) (PO ₂ H ₂ ) ₂ (H ₄ L) as a ligand are used for applying high-quality coatings of copper, nickel, zinc, cadmium, noble and other metals (Haynes RT, Irani RR, Langguth RP US 3475293 (publ. 1969). Kowalski X. US 3706634 (publ. 1972). Kowalski X. US 3706635 (publ. 1972). Nobel FI, Yoen LC US 3833486 (publ. 1974). Kowalski X. US 3914162 (publ. 1975). Kowalski X. US 3928147 (publ. 1975). Mallory CO., Johnson CE DE 2942792 (publ. 1980). Tomaszewski LC, Tremmel RA US 4462874 (publ. 1984). Berezina S.I., Sageeva PM, Amirov PP // Protection of metals, 1987, V.23, No. 6, S.1032. Gan Y. // Plating and Surface Finishing, 1992, V.79, No. 6, P.81. Ratajewicz Z., Saneluta C // Plating and Surface Finishing, 1999, V.86, No. 7, P.50. Lviv BM, Afonin E. G. RU 2276205 (publ. 2006). Lvovsky V.M., Afonin E.G. RU 2293144 (publ. 2007)).

Anion of 1-hydroxyethane-1,1-diphosphonic acid is a toxic substance (Hygienic standards GN 2.1.5.2280-07 “Maximum permissible concentrations (MPC) of chemicals in the water of water bodies for drinking, cultural and domestic water use.” Karamzin KB Comparative assessment of the toxicity and hazard of reagents used in hot water supply systems. Abstract of thesis ... Candidate of Medical Sciences. - M. 2007). In addition, the anion of 1-hydroxyethane-1,1-diphosphonic acid binds metal cations into thermodynamically strong, often water-soluble complexes, which prevents the precipitation of metal cations in the form of hydroxides or other water-insoluble compounds in the processes of reagent and physico-chemical cleaning waste solutions and wastewater. Therefore, the anion of 1-hydroxyethane-1,1-diphosphonic acid, which is part of the spent solutions of electrochemical and chemical coatings with metals, other aqueous solutions, must be neutralized. One of the methods for neutralizing the anion of 1-hydroxyethane-1,1-diphosphonic acid is its destruction by oxidation to orthophosphate, which is non-toxic and does not have the ability to bind metal cations to soluble complexes.

A known method of destroying the anion of 1-hydroxyethane-1,1-diphosphonic acid in waste products, comprising treating with concentrated nitric acid a liquid waste product containing a metal cation and an anion of 1-hydroxyethane-1,1-diphosphonic acid (Horvits E.F., Getron RK, Nash KL Method for the extraction of metal ions. Patent of the Russian Federation No. 2091311. Publ. 1997). The method does not provide for the use of production waste as an oxidizing agent. The disadvantage of this method is the very stringent conditions for the oxidation reaction, the high duration of the process and the release of toxic nitrogen oxides.

A known method of destroying the anion of 1-hydroxyethane-1,1-diphosphonic acid, comprising treating an aqueous solution containing the anion of 1-hydroxyethane-1,1-diphosphonic acid with a 4% solution of potassium permanganate at room temperature or by boiling the solution (Martynov A .P., Gorodetsky VI. Collection "Modern methods of analysis of industrial materials and natural objects. Materials of a scientific and technical short-term seminar. Society" Knowledge ". Leningrad DNTP, 1992, 4.1, P. 46). The destruction of the anion of 1-hydroxyethane-1,1-diphosphonic acid to orthophosphate is carried out during the chemical analysis of the electrolyte coating with zinc-iron alloy containing 0.1-0.4 g / l of anion of 1-hydroxyethane-1,1-diphosphonic acid. The disadvantage of this method is the need for high material costs for the reagent-oxidizing agent potassium permanganate.

A known method of destroying the anion of 1-hydroxyethane-1,1-diphosphonic acid in waste products, comprising treating a liquid waste product containing the anion of 1-hydroxyethane-1,1-diphosphonic acid with chromium (+6) in an acidic medium (Afonin E.G. A method of oxidative decomposition of the anion of 1-hydroxyethane-1,1-diphosphonic acid in an aqueous solution, RF Patent No. 2363666, publ. 2009). The method allows to convert into orthophosphate more than 99% of the anion of 1-hydroxyethane-1,1-diphosphonic acid and use galvanic waste containing chromium (+6) as an oxidizing agent. The method does not provide for the use of spent etching solutions of printed circuit boards containing ammonium peroxodisulfate as an oxidizing agent.

A known method of destroying the anion of 1-hydroxyethane-1,1-diphosphonic acid, comprising treating with an oxidizing agent an aqueous solution containing the anion of 1-hydroxyethane-1,1-diphosphonic acid. An ozone-oxygen mixture is used as an oxidizing agent in the presence of a catalyst - iron (+3), cerium (+3), zirconium (+4), manganese (+2) at pH 14 and a temperature of 90 ° C (Vyatkin V.E., Lapitskaya O .V., Legin V.K., Rzhevtsev N.P., Senchillo V.Kh. Wastewater treatment from phosphonic acids and their salts (Auth. Certificate of the USSR No. 979279. Publ. 1982). The method allows for the destruction of the anion of 1-hydroxyethane-1,1-diphosphonic acid by 88-99%. The disadvantage of this method is the need for high material costs for the reagent-oxidizer, catalyst. The method does not include the use of industrial waste as an oxidizing agent of the 1-hydroxyethane-1,1-diphosphonic acid anion.

A known method of destroying the anion of 1-hydroxyethane-1,1-diphosphonic acid, comprising treating an aqueous solution containing the anion of 1-hydroxyethane-1,1-diphosphonic acid with an oxidizing reagent, which uses hydrogen peroxide in the presence of a vanadium catalyst (+ 5) or osmium tetraoxide (Appelman E.N., Jache AW, Mimtean JV The vanadium (V) -catalyzed oxidation of (1-hydroxyethylidene) bisphosphonic acid, CH ₃ C (OH) (PO ₃ H ₂ ) ₂ , by hydrogen peroxide in aqueous solution. // Journal of Molecular Catalysis A: Chemical, 1996, V.106, P.197). The disadvantage of this method is the need for high material costs for hydrogen peroxide and for the catalyst. The method does not provide for the destruction of the anion of 1-hydroxyethane-1,1-diphosphonic acid in the composition of the spent solutions, and also does not provide for the use of industrial waste to destroy the anion of 1-hydroxyethane-1,1-diphosphonic acid.

A known method of destroying microgram amounts of anion of 1-hydroxyethane-1,1-diphosphonic acid to orthophosphate as a preparatory operation for the quantitative chemical analysis of cooling water of thermal power plants (Maklakova V.P., Zalozhkova K.I. // Factory Laboratory, 1975, T .41, No. 8, P.944) by heating with ammonium peroxodisulfate in concentrated sulfuric acid for at least 20 minutes. The method allows for the quantitative conversion of the anion of 1-hydroxyethane-1,1-diphosphonic acid to orthophosphate. The disadvantage of this method is the very stringent conditions of the process, which does not allow it to be used to destroy macro quantities of the anion of 1-hydroxyethane-1,1-diphosphonic acid, as well as the need for high material costs for the reagent-oxidizing agent ammonium peroxodisulfate.

Closest to the claimed method is the destruction of the anion of 1-hydroxyethane-1,1-diphosphonic acid in waste products, including the treatment of peroxodisulfate liquid production waste containing a metal cation and anion 1-hydroxyethane-1,1-diphosphonic acid (Horvits E.F. , Getron, R.K., Nash, K.L., Method for the Extraction of Metal Ions (RF Patent No. 2091311, Publ. 1997). The method does not provide for the use of production waste as an oxidizing agent. The disadvantage of this method is the need for high material costs for the reagent-oxidizer peroxodisulfate.

The aim of the claimed invention is to reduce material costs for the neutralization of toxic waste products containing a metal cation and anion of 1-hydroxyethane-1,1-diphosphonic acid, expanding the arsenal of methods for utilizing spent etching solutions of printed circuit boards containing ammonium peroxodisulfate.

This goal is achieved in that the method of destroying the anion of 1-hydroxyethane-1,1-diphosphonic acid in waste products includes the treatment of peroxodisulfate liquid waste products containing a metal cation and anion 1-hydroxyethane-1,1-diphosphonic acid. New in this method is that a waste product is used as a source of peroxodisulfate — an spent solution for etching printed circuit boards containing ammonium peroxodisulfate in an amount of at least 2.0 mol per 1.0 mol of 1-hydroxyethane-1,1-diphosphonic acid anion. It is advisable to use a spent solution for etching printed circuit boards containing copper (+2), ammonia, ammonium sulfate, ammonium peroxodisulfate as the main components or a spent solution for etching printed circuit boards containing copper (+2), sulfuric acid, ammonium sulfide as the main components, ammonium peroxodisulfate.

A liquid production waste is, for example, a spent electroplating copper plating solution containing copper (+2) as the main components, 1-hydroxyethane-1,1-diphosphonic acid anion, or a spent galvanizing solution containing zinc as the main components (+ 2), an anion of 1-hydroxyethane-1,1-diphosphonic acid, or an spent galvanic nickel plating solution containing nickel (+2), the anion of 1-hydroxyethane-1,1-diphosphonic acid, or a spent chemical copper plating, containing copper (+2) as the main components, 1-hydroxyethane-1,1-diphosphonic acid anion, a reducing agent, a reducing agent oxidation product, or a spent chemical nickel solution containing nickel (+2), anion as the main components 1-hydroxyethane-1,1-diphosphonic acid, a reducing agent, an oxidation product of a reducing agent. The peroxodisulfate treatment of the liquid waste product containing a metal cation and an anion of 1-hydroxyethane-1,1-diphosphonic acid is preferably carried out in the presence of a homogeneous catalyst.

The method of destruction of the anion of 1-hydroxyethane-1,1-diphosphonic acid consists in mixing the waste product - the spent solution of an electrochemical or chemical coating with metals, which contains a complex metal compound with the anion of 1-hydroxyethane-1,1-diphosphonic acid, with another waste product - a spent solution for etching printed circuit boards containing ammonium peroxodisulfate in an amount sufficient to completely oxidize the anion of 1-hydroxyethane-1,1-diphosphonic acid with peroxodisulfate. If necessary, acid or alkali is added to the resulting solution to achieve the optimum pH value, an oxidation catalyst is introduced, or the solution is heated. The reaction solution is maintained for a time sufficient to achieve a high degree of conversion of the 1-hydroxyethane-1,1-diphosphonic acid anion to orthophosphate.

The claimed method is based on reactions, for example:

Spent metal coating solutions (copper, zinc, nickel, iron, cobalt, cadmium, tin, lead, antimony, silver, gold, platinum group metals) by the galvanic method contain metal salt and 1-hydroxyethane-1,1- anion as the main components diphosphonic acid, for example:

Copper sulphate 0.1-0.5 mol / L Potassium or sodium 1-hydroxyethane-1,1-diphosphonate 0.1-2.0 mol / L pH 6-13, or Zinc sulphate 0.1-0.5 mol / L Potassium or sodium 1-hydroxyethane-1,1-diphosphonate 0.15-2.0 mol / L Organic supplement 0.001-1.0 mol / L pH 6-13.5, or Nickel sulfate 0.05-0.5 mol / l Potassium or sodium 1-hydroxyethane-1,1-diphosphonate 0.1-2.0 mol / L Organic supplement 0.001-1.0 mol / L pH 7-12

The spent metal coating solutions (copper, nickel, iron, cobalt, silver, gold, platinum, palladium) chemically contain a metal salt, anion 1-Hydroxyethane-1,1-diphosphonic acid and additionally include a reducing agent and oxidizing products of a reducing agent, for example:

Copper Sulfate (+2) 0.01-0.1 mol / L Potassium 1-hydroxyethane-1,1-diphosphonate 0.1-0.3 mol / L Formaldehyde 0.10-1.0 mol / L Sodium formate 0.10-2.0 mol / L pH 4-14, or Nickel Sulphate (+2) 0.01-0.2 mol / L Potassium 1-hydroxyethane-1,1-diphosphonate 0.1-0.4 mol / L Sodium Hypophosphite 0.05-0.2 mol / L Sodium phosphite 0.1-1.0 mol / L Sodium Acetate 0.1-0.2 mol / L pH 2-7

When peroxodisulfate solutions for etching printed circuit boards are used, peroxodisulfate is consumed in reactions

Cu + (NH ₄ ) ₂ S ₂ O ₈ → CuSO ₄ + (NH ₄ ) ₂ SO ₄

Cu + (NH ₄ ) ₂ S ₂ O ₈ + 4NH ₃ → [Cu (NH ₃ ) ₄ ] SO ₄ + (NH ₄ ) ₂ SO ₄ ,

and the solution accumulates the product of the reduction of ammonium peroxodisulfate - ammonium sulfate. The etching solution loses its technological properties when it contains still high concentrations of peroxodisulfate. Spent printed circuit board etching solutions containing ammonium peroxodisulfate have the composition:

Copper (+2) 0.15-0.7 mol / L Ammonium sulfate 0.2-1.0 mol / l Ammonium peroxodisulfate 0.1-0.9 mol / L Sulphuric acid 0.1-0.4 mol / l, or Copper (+2) 0.15-0.35 mol / L

Ammonium sulfate 0.2-0.45 mol / L Ammonium peroxodisulfate 0.05-0.25 mol / L Ammonia 3.5-4.5 mol / L

The destruction of the anion of 1-hydroxyethane-1,1-diphosphonic acid in industrial wastes containing metal complexes (copper, zinc, nickel, etc.) with this anion occurs due to the oxidation of the organic part of the complexes by a strong oxidizing agent - peroxodisulfate ion S ₂ O ₈ ^2- forming part of copper-containing waste solutions etching printed circuit boards: peroksodisulfatnyh ammonia-containing complex of copper (2) with ammonia, ammonia, ammonium peroxodisulfate, its reduction product - ammonium sulfate, additives (e.g., glycerol) or sulphate-p roksodisulfatnyh containing copper ions (+2), sulfuric acid, peroxodisulphate ammioniya, its reduction product - ammonium sulfate.

Peroxodisulfate ion is a strong oxidizing agent in acidic, neutral and alkaline environments:

$$S_2{\mathrm{<figure-callout\; id="8"\; label="O"\; filenames="00000006.png"\; state="\{\{state\}\}">O</figure-callout>}}_8{}^{2-}+2\overline{e}\leftrightarrow 2S{O}_{\mathrm{four}}{}^{2-}$$

E ° = + 2.01 V, $$S_2{\mathrm{<figure-callout\; id="8"\; label="O"\; filenames="00000006.png"\; state="\{\{state\}\}">O</figure-callout>}}_8{}^{2-}+2H^{+}+2\overline{e}\leftrightarrow 2HS{O}_{\mathrm{four}}{}^{-}$$

E ° = + 2.12 V

(Greenwood N., Ernshaw A. Chemistry of elements. T.2. - M .: BINOM. Laboratory of knowledge. 2008. P.65). Potassium and ammonium peroxodisulfates oxidize hydrocarbons, alcohols, aldehydes and ketones, carboxylic acids, amino acids, amines, amino alcohols and a number of other organic substances (Berlin A.A., Kislenko V.N. Oxidation of organic compounds with persulfate. - Lvov: Svit. 1991. - 140 p.). With a large excess of oxidizing agent, some of them can be converted into carbon dioxide and water.

Peroxodisulfate ion in an aqueous solution gradually spontaneously breaks down (Berlin A.A., Kislenko V.N. Oxidation of organic compounds by persulfate. - Lviv: Sweet. 1991. - 140 p.):

S ₂ O ₈ ^2- + H ₂ O → SO ₅ ^2- + SO ₄ ^2- + 2Н ⁺ S ₂ O ₈ ^2- + 2OH ^- → SO ₅ ^2- + SO ₄ ^2- + H ₂ O (pH <3, pH> 13) S ₂ O ₈ ^2- → 2SO ₄ ^{· -} (pH3-13)

therefore, the oxidation of organic matter can produce both peroxodisulfate ion S ₂ O ₈ ^2- and peroxomonosulfate ion SO ₅ ^2- and the radical anion sulfate SO ₄ ^{· -} .

According to experimental data, the ability of the peroxodisulfate ion to oxidize the 1-hydroxyethane-1,1-diphosphonic acid anion depends on the concentrations of hydrogen ions, peroxodisulfate, the 1-hydroxyethane-1,1-diphosphonic acid anion in solution, temperature, and other factors. The thermodynamic and kinetic stability of complexes with metal cations, which include this anion, have a great influence on the speed, nature and completeness of the oxidation by peroxodisulfate of the anion of 1-hydroxyethane-1,1-diphosphonic acid. Therefore, for the effective destruction of the production of the anion of 1-hydroxyethane-1,1-diphosphonic acid, complexed with a metal cation, by oxidizing it with peroxodisulfate in the reaction solution, it is necessary to create optimal conditions (pH, temperature, molar ratio of reactants, catalyst, etc.) .

Figure 1-4 shows examples of kinetic curves for the oxidation reactions of the 1-hydroxyethane-1,1-diphosphonic acid anion with peroxydisulfate (graphs of the concentration of the oxidizing agent (the sum of the concentrations of peroxodisulfate, peroxomonosulfate and hydrogen peroxide) versus reaction time) under various conditions.

Figure 1 The change in the concentration of the oxidizing agent over time during the oxidation of the anion of 1-hydroxyethane-1,1-diphosphonic acid with peroxodisulfate in a sulfuric acid medium: 1 - C ⁰ (S ₂ O ₈ ^2- ) = 0,100 mol / l, C ⁰ (H ₂ SO ₄ ) = 0.50 mol / l, t = 24-28 ° C; 2 - C ⁰ (S ₂ O ₈ ^2- ) = 0.100 mol / L, C ⁰ (H ₂ SO ₄ ) = 0.50 mol / L, C ⁰ (H ₄ L) = 0.01 mol / L, t = 23-28 ° C; 3 - C ⁰ (S ₂ O ₈ ^2- ) = 0.100 mol / L, C ⁰ (H ₂ SO ₄ ) = 0.50 mol / L, C ⁰ (H ₄ L) = 0.01 mol / L, C (Mn ²⁺ ) = 0.005 mol / L, t = 23-30 ° C; 4 - C ⁰ (S ₂ O ₈ ^2- ) 0.100 mol / L, C ⁰ (H ₂ SO ₄ ) = 0.50 mol / L, C ⁰ (H ₄ L) = 0.01 mol / L, C ( Cu ²⁺ ) = 0.005 mol / L, t = 23-27 ° C.

In an aqueous sulfuric solution, the anion of 1-hydroxyethane-1,1-diphosphonic acid greatly slows down the self-decomposition of the S ₂ O ₈ ^2- and SO ₅ ^2- anions (Fig. 1, kinetic curves 1 and 2), and the addition of the Cu ²⁺ cation ( to a small degree) and Mn ²⁺ (to a much greater extent) accelerates the oxidation reaction of 1-hydroxyethane-1,1-diphosphonic acid anion with peroxodisulfate to orthophosphate (Fig. 1, kinetic curves 3 and 4).

Figure 2 The change in the concentration of the oxidizing agent over time during the self-decomposition of peroxodisulfate in the sulfuric acid medium: 5 - С ⁰ (S ₂ O ₈ ^2- ) = 0.100 mol / L, C ⁰ (H ₂ SO ₄ ) = 0.50 mol / L, t = 28 ° C; 6 - C ° (S ₂ O ₈ ^2- ) = 0.100 mol / L, C ⁰ (H ₂ SO ₄ ) = 0.50 mol / L, C (Ag ⁺ ) = 0.001 mol / L, t = 29 ° C .

Figure 3 The change in the concentration of the oxidizing agent over time during the oxidation of the anion of 1-hydroxyethane-1,1-diphosphonic acid with peroxodisulfate in a sulfuric acid medium: 7 - C ⁰ (S ₂ O ₈ ^2- ) = 0,100 mol / l, C ⁰ (H ₂ SO ₄ ) = 0.50 mol / L, C ⁰ (H4L) = 0.01 mol / L, t = 29 ° C; 8 - C ⁰ (S ₂ O ₈ ^2- ) = 0.100 mol / L, C ⁰ (H ₂ SO ₄ ) = 0.50 mol / L, C ⁰ (H ₄ L) = 0.01 mol / L, C (Ag ⁺ ) = 0.001 mol / L, t = 29 ° C; 9 - C ⁰ (S ₂ O ₈ ^2- ) = 0.100 mol / L, C ⁰ (H ₂ SO ₄ ) = 0.50 mol / L, C ⁰ (H ₄ L) = 0.0 1 mol / L, C (Ag ⁺ ) = 0.005 mol / L, t = 29 ° C.

As can be seen from FIGS. 2 and 3, in an aqueous sulfuric solution, silver cations accelerate both the self-decomposition of S ₂ O ₈ ^2- and SO ₅ ^2- anions, and, to a much greater extent, the oxidation reaction of 1-hydroxyethane-1 by these anions, 1-diphosphonate ion.

Figure 4 The change in the concentration of the oxidizing agent over time during the oxidation of the anion of 1-hydroxyethane-1,1-diphosphonic acid with peroxodisulfate in a neutral medium (pH 6.8 - phosphate buffer): 10 - C ⁰ (S ₂ O ₈ ^2- ) = 0,100 mol / l, t = 24-28 ° C; 11 - C ⁰ (S ₂ O ₈ ^2- ) = 0,100 mol / L, C ⁰ (H ₄ L) = 0,01 mol / L, t = 24-30 ° C, 12 - C ⁰ (S ₂ O ₈ ^2- ) = 0.100 mol / L, C ⁰ (H ₄ L) = 0.01 mol / L, C ⁰ (Mn ²⁺ ) = 0.005 mol / L, t = 24-28 ° C; 13 - C ⁰ (S ₂ O ₈ ^2- ) = 0.100 mol / L, C ⁰ (H ₄ L) = 0.01 mol / L, C ⁰ (VO ²⁺ ) 0.005 mol / L, t = 23-28 ° C.

In a neutral medium, the oxidation of the anion of 1-hydroxyethane-1,1-diphosphonic acid with peroxodisulfate without a catalyst proceeds at a noticeable rate (Fig. 4, kinetic curves 10 and 11), and VO ²⁺ and Mn ²⁺ cations are inhibitors of the reaction under these conditions ( 4, kinetic curves 12 and 13).

Example 1

20 ml of the spent electroplating copper plating solution are mixed with a concentration of copper sulfate 0.20 mol / L, potassium 1-hydroxyethane-1,1-diphosphonate 0.50 mol / L, ethylene diamine 0.001 mol / L (pH 7.6) and 130 ml spent a solution of sulfuric acid peroxodisulfate etching of printed circuit boards with a concentration of copper sulfate 0.24 mol / L, ammonium sulfate 1.4 mol / L, ammonium peroxodisulfate 0.18 mol / L, sulfuric acid 0.25 mol / L. The resulting solution was incubated for 5.5 hours at a temperature of 75-80 ° C. The degree of conversion of the anion of 1-hydroxyethane-1,1-diphosphonic acid to orthophosphate is 83%.

Example 2

Mix 20 ml of the spent galvanizing solution with a concentration of zinc sulfate 0.22 mol / l, 1-hydroxyethane-1,1-potassium diphosphonate 0.80 mol / l, SAS 0.002 mol / l (pH 9.9) and 1000 ml spent a solution of sulfuric acid peroxodisulfate etching of printed circuit boards with a concentration of copper sulfate 0.18 mol / L, ammonium sulfate 1.2 mol / L, ammonium peroxodisulfate 0.16 mol / L, sulfuric acid 0.20 mol / L. A solution of 1.2 g of silver nitrate in 10 ml of water is added to the resulting solution with stirring. The solution was incubated for 3 hours at a temperature of 80-90 ° C. The conversion of 1-hydroxyethane-1,1-diphosphonic acid anion to orthophosphate is 97%.

Example 3

Mix 20 ml of the spent solution of galvanic nickel plating with a concentration of nickel sulfate 0.20 mol / l, 1-hydroxyethane-1,1-potassium diphosphonate 0.75 mol / l (pH 7.1) and 830 ml of the spent solution of ammonia-peroxodisulfate etching printed boards with a concentration of copper sulfate 0.20 mol / L, ammonium sulfate 0.32 mol / L, ammonium peroxodisulfate 0.18 mol / L, ammonia 3.9 mol / L. A solution of 2.0 g of silver nitrate in 40 ml of water is added with stirring. The resulting solution was incubated for 48 days at a temperature of 25-30 ° C. The degree of conversion of the anion of 1-hydroxyethane-1,1-diphosphonic acid to orthophosphate 99%.

Example 4

20 ml of the spent electroplating copper plating solution are mixed with a concentration of copper sulfate 0.18 mol / l, potassium 1-hydroxyethane-1,1-diphosphonate 0.56 mol / l, diethylene triamine 0.0012 mol / l (pH 7.8), 220 ml of waste solution of sulfuric acid peroxodisulfate etching of printed circuit boards with a concentration of copper sulfate 0.25 mol / L, ammonium sulfate 0.80 mol / L, ammonium peroxodisulfate 0.50 mol / L, sulfuric acid 0.30 mol / L and 10 ml 2 , 2% solution of silver nitrate. The resulting solution was incubated for 12 days at a temperature of 25-30 ° C. The degree of conversion of the anion of 1-hydroxyethane-1,1-diphosphonic acid to orthophosphate 99%.

As can be seen from the above examples, the claimed method allows the destruction of more than 99% of the anion of 1-hydroxyethane-1,1-diphosphonic acid contained in spent solutions of galvanic and chemical coatings with metals, to non-toxic products by peroxodisulfate oxidation. At the same time, the waste from the production of printed circuit boards is used as an oxidizing reagent — an spent solution of sulfuric acid peroxodisulfate etching or an exhausted solution of ammonia peroxodisulfate etching. Due to the mutual neutralization of the two types of liquid production waste, the material costs of neutralization are significantly reduced while maintaining the neutralization completeness.

Claims (11)

1. The method of destruction of the anion of 1-hydroxyethane-1,1-diphosphonic acid in waste products, comprising treating with peroxodisulfate a liquid waste product containing a metal cation and an anion of 1-hydroxyethane-1,1-diphosphonic acid, characterized in that as a source of peroxodisulfate they use waste from electronic production - a spent solution for etching printed circuit boards containing ammonium peroxodisulfate in an amount of at least 2.0 mol per 1.0 mol of anion 1-hydroxyethane-1,1-diphosphonic acid. 2. The method according to claim 1, characterized in that the spent solution for etching the printed circuit boards contains copper (+2), ammonium sulfate, ammonium peroxodisulfate, ammonia as main components. 3. The method according to claim 1, characterized in that the spent solution for etching the printed circuit boards contains copper (+2), ammonium sulfate, ammonium peroxodisulfate, sulfuric acid as main components. 4. The method according to claim 1, characterized in that the liquid waste product containing a metal cation and an anion of 1-hydroxyethane-1,1-diphosphonic acid, is a spent solution of galvanic copper plating containing copper (+2) as the main components, anion of 1-hydroxyethane-1,1-diphosphonic acid. 5. The method according to claim 1, characterized in that the liquid waste product containing a metal cation and an anion of 1-hydroxyethane-1,1-diphosphonic acid is a spent galvanic galvanizing solution containing zinc (+2) as the main components, anion of 1-hydroxyethane-1,1-diphosphonic acid. 6. The method according to claim 1, characterized in that the liquid waste product containing a metal cation and the anion of 1-hydroxyethane-1,1-diphosphonic acid, is a spent solution of galvanic nickel plating containing nickel (+2) as the main components, anion of 1-hydroxyethane-1,1-diphosphonic acid. 7. The method according to claim 1, characterized in that the liquid waste product containing a metal cation and the anion of 1-hydroxyethane-1,1-diphosphonic acid, is an spent solution of chemical copper plating containing copper (+2) as the main components, 1-hydroxyethane-1,1-diphosphonic acid anion, reducing agent, oxidizing agent of reducing agent. 8. The method according to claim 1, characterized in that the liquid waste product containing a metal cation and an anion of 1-hydroxyethane-1,1-diphosphonic acid is an spent chemical nickel plating solution containing nickel (+2) as the main components, 1-hydroxyethane-1,1-diphosphonic acid anion, reducing agent, oxidizing agent of reducing agent. 9. The method according to claim 1, characterized in that the treatment with liquid peroxodisulfate production waste containing a metal cation and anion of 1-hydroxyethane-1,1-diphosphonic acid is carried out in the presence of a homogeneous catalyst. 10. The method according to claim 9, characterized in that silver (+1) is used as a catalyst. 11. The method according to claim 9, characterized in that manganese (+2) is used as a catalyst.

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