RU2157855C2 - Method of gold recovery from gold-containing highly mineralized chloride solutions - Google Patents

Abstract

FIELD: recovery of gold from highly mineralized solutions, for instance, reusable solutions of potassium and potassium-magnesium production, and in- passing recovery of gold from process solutions. SUBSTANCE: method includes treatment of highly mineralized solution with gold content of, at least, 10 mcg/1 with flocculant based on polyacrylamide and oxyethylated aliphatic acid in weight ratio of 1(2-3) in amount of 0.2 mg/1 and 0.4-0.6 mg/1, respectively, and separation by flotation. Then, solution is treated with mixture of butyl xanthate and AEROFLOT composition in weight ratio of 1:1 and in amount of 10-20 mg/1 with subsequent separation of gold- containing concentrate by flotation. EFFECT: higher recovery of gold from highly mineralized gold-containing chloride solutions and produced concentrate rich in gold. 2 cl, 1 tbl, 3 ex

Description

 The invention relates to the technology of hydrometallurgy of precious metals and can be applied at enterprises processing potash ores for the associated extraction of gold from industrial solutions. In addition to the main components (sylvin, halite), potassium ores contain water-insoluble carbonate-clay minerals (n.o.), as well as microinclusions of precious metals / 1 /.

According to GIREDMET, ~ 80% of gold in potash ores is present in the form of colloidal gold. In a chlorinated system with a high Cl ^- predominance, soluble anionic complex ions of the AuCl ₄ ^- type ^{are formed} , which can interact with cationic surfactants to produce poorly soluble sublates, and also coprecipitate on the surface of positively charged particles of carbonates, silicates, metal hydroxides and float with anionic surfactants. These poorly soluble precipitates, colloids, and molecules in the presence of flotation reagents under aeration conditions can actively float. It is also possible the formation of inactive complex gold compounds in the presence of organic acids (humic, fulvic acids), which have low flotation activity.

The closest in technical essence is a method for the extraction of gold from gold-containing highly mineralized chloride solutions, including processing solutions with alkali or hydrochloric acid to achieve a pH of 5.8 - 7.2, a reagent such as chloride or Fe ²⁺ sulfate and alkali metal salts of dialkyldithiocarbamic acid to form finely dispersed sparingly soluble complex compounds with their subsequent sedimentation and separation of a gold-bearing precipitate / 2 /.

 The disadvantage of this method is the use of pH adjusting reagents, the introduction of which can adversely affect the processes of obtaining potash products, the low selectivity of the precipitation process and, as a result, the low gold content in the precipitate, the low rate of deposition of fine particles.

 The technical result of the invention is to increase the extraction of gold from highly mineralized chloride solutions and obtain a richer in gold concentrate.

 The technical result of the inventions is achieved by the fact that in the method for extracting gold from gold-containing highly mineralized chloride solutions by treating them with reagents and isolating a gold-containing precipitate, highly mineralized working solutions of flotation and chemical potash production with a gold content of at least 10 μg / l are used - flotation working brines (I variant ) at the beginning with a flocculant based on polyacrylamide and fatty acids (ethoxylated fatty acids (demulsifier oil emulsions). - TU 38.101417-88) a mass ratio of 1: 2-3 in an amount of 0.2 mg / l, 0.4-0.6 mg / l, respectively, and separated by flotation, and then the purified solution is treated with a mixture of butyl xanthate and Aeroflot in a mass ratio of 1: 1 and in the amount of 10-20 mg, followed by the separation of the gold-containing concentrate by flotation, while the second processing stage (option II) is used for working solutions of chemical potash or carnallite production.

The method is as follows. The starting material used is a potassium mill recycling solution (highly mineralized chloride solution), for example, the flotation factory BKRU-2 of OJSC Uralkali, which is a solution saturated with KCl and NaCl (at a temperature of 20 - 25 ^o C, density 1.235 - 1.236 kg / m ³ ) containing gold in an amount of not less than 10 μg / l, as well as suspended particles of minerals n.o. and salts in an amount of 130 - 400 mg / l; and surfactants are the reagents used to obtain KCl. The circulating solution is pre-treated with aqueous solutions of reagents (0.1% aqueous solution of polyacrylamide flocculant in an amount of 0.2 kg / l and 2% emulsion OFA in the amount of 0.4 - 0.6 mg / l) with stirring for 1 to 2 minutes and carry out the first flotation stage in a column-type pneumatic machine with a specific air flow rate of 0.5 - 0.75 m ³ / m ³ chamber volume. Duration of flotation is 5-10 minutes. The amount of gold recovery ~ 60 - 65%.

In order to recover gold, the second stage of flotation is carried out: treatment with sulfhydryl collectors (1% aqueous solution in an amount of 10 - 20 g / m ^{3 of a} solution of the 1st stage) with preliminary conditioning for 10 minutes. Flotation is carried out under the same conditions as the 1st stage, for 20 to 25 minutes.

 Example 1. At the same time, a reverse solution of a flotation plant BKRU-2 with a content of 0.076 mg / l (76 μg / l) of gold, a flocculant polyacrylamide in an amount of 0.2 mg / l in the form of a 0.1% aqueous emulsion and an FFA in the amount of 0.6 mg / l in the form of a 2% aqueous emulsion. Mixing is carried out for 1 min and the material is fed to the flotation. Flotation time 10 min. The solution after the first stage is treated with a mixture of butyl xanthate and Aeroflot (dithiophosphate) in a mass ratio of 1: 1 in the amount of 10 mg / l in the form of a 1% aqueous emulsion. Stirred for 10 minutes and served the solution in the second stage of flotation. Flotation time ~ 25 min.

 The results of flotation separation (op. 1) of gold are presented in the table.

 Example 2. At the same time, a BKRU-2 flotation factory solution containing 0.076 mg / l of gold and a mixture of butyl xanthate and Aeroflot (dithiophosphate) at a weight ratio of 1: 1 in an amount of 20 mg / l in the form of 1% are simultaneously fed into a mechanical mixer water emulsion. Stirred for 10 minutes and feed the material to the flotation. Flotation time 25 min. The separation results (op. 2) are shown in the table.

 Example 3. At the same time, a reverse solution of a chemical factory BKPRU-1 of Uralkali OJSC containing 0.099 mg / l of gold and a mixture of butyl xanthate and Aeroflot (dithiophosphate) in the form of a 1% aqueous emulsion with a mass ratio of 1: 1 in the amount of 20 mg / l. After stirring for 10 minutes, the solution enters the flotation. Flotation time 25 min.

 The results of the analysis are presented in the table (op. 3).

List of sources used
1. Smetannikov A. F., Kudryashov A.I. The content and distribution of gold, silver and platinum in sylvinite of the Verkhnekamsk deposit. - Geochemistry, 1995, N 9, p. 1348 - 1350.

 2. Application N 97102286/02 (002507). RU 2109827 C1 publ. 04/27/98. The method of extracting gold from gold-containing highly mineralized solutions for the production of potash fertilizers. Class c 22 B 11/00.

 3. Zelenov V.I. Methodology for the study of gold and silver ores. - M .: Nedra, 1989, p. 309.

Claims (2)

 1. A method of extracting gold from gold-containing highly mineralized chloride solutions, comprising treating with reagents and isolating a gold-containing precipitate, characterized in that the highly mineralized working solution of flotation potassium production with a gold content of at least 10 μg / l is treated with a flocculant based on polyacrylamide and OLC in a weight ratio of 1: 2 - 3 in the amount of 0.2 mg / l of polyacrylamide and 0.4 - 0.6 mg / l of fatty acids and separated by flotation, after which the solution is treated with a mixture of butyl xanthate and Aeroflot in asses the ratio 1: 1 and in an amount of 10 - 20 mg / L, followed by separation of gold flotation concentrate.  2. A method of extracting gold from gold-containing highly mineralized chloride solutions, comprising treating with reagents and isolating a gold-containing precipitate, characterized in that the highly mineralized working solution of a chemical potassium or carnallite production with a gold content of at least 10 μg / l is treated with a mixture of butyl xanthate and Aeroflot in bulk 1: 1 ratio in an amount of 10 - 20 mg / l, followed by the separation of a gold-containing precipitate by flotation.

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