Bioleaching: Validation of the Extraction of Precious Metals Through Selective Recovery of Iron, Copper and Zinc
Zambrano Johanna,
Zambrano Johnny
Issue:
Volume 6, Issue 4, December 2021
Pages:
73-78
Received:
20 October 2021
Accepted:
11 November 2021
Published:
17 November 2021
Abstract: In Ecuador, large gold deposits were discovered in the areas of Nambija and Ponce Enríquez, but they contain metal sulfides that, when exposed to the action of air and water, intervene in a series of physical, chemical and biological phenomena. The oxidation of sulfides to sulfates occurs by the catalytic action of bacteria, in addition to the production of sulfuric acid that dissolves heavy metals such as iron, copper and zinc; a process known as bioleaching. These solutions, with a high level of acidity, are carried away by water currents or runoff, becoming a great contaminant of water and soil of the surrounding sector. Acid mine drains are one of the main problems of environmental pollution; the mining deposits are located in areas of great biodiversity. In these areas there are births of water used for human consumption, agriculture and mining work; the mismanagement of tailings, tailings and sands that are discharged into rivers and streams generate serious environmental damage. The objective of the work is to use selective precipitation to recover iron, copper and zinc from acid solutions produced by bioleaching during the extraction of precious metals at the laboratory level and from acid drainage of natural mine, to comply with environmental regulations regarding the discharge of effluents and reduce the effect of environmental pollution produced by acid mine drains. This investigation presents the conditions for a successful individual recovery of the main base metals contained in a bioleaching solution with high copper, zinc, and iron concentrations by pH-based selective precipitation. Tests were made with standard solutions of known concentrations of copper, iron, lead, and zinc and by titration the concentrations were checked, which allowed to validate the volumetric titration method. The selective precipitation of heavy metals was carried out in three phases using real acid main drainage and bioleaching solutions generated at the laboratory. The first phase in a pH range of 2 to 4 to recover iron; the second phase in a pH range of 4 to 6 to recover copper; and the third phase in a pH range of 6 to 10 to recover zinc. The selective precipitation allowed the heavy metals to be completely removed from the solution or to achieve concentrations below the maximum allowable limit to be discharged to a body of water or public sewer. Validation of SOLBIO 2 and Orenas bioleaching solutions was performed.
Abstract: In Ecuador, large gold deposits were discovered in the areas of Nambija and Ponce Enríquez, but they contain metal sulfides that, when exposed to the action of air and water, intervene in a series of physical, chemical and biological phenomena. The oxidation of sulfides to sulfates occurs by the catalytic action of bacteria, in addition to the prod...
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Research on Obtaining Gadolinium Oxide from Waste Technologies for Processing of Uranium-gadolinium Containing Materials
Manarbek Kylyshkanov,
Natalya Yaroshenko,
Galina Gusakova,
Anna Dorn,
Andrey Gofman,
Yuri Varyvdin
Issue:
Volume 6, Issue 4, December 2021
Pages:
79-83
Received:
10 September 2021
Accepted:
9 October 2021
Published:
27 November 2021
Abstract: One of the activities of the Uranium production of JSC "UMP" is the processing of hard-to-open uranium-gadolinium-containing scraps. When processing materials of this type, after their dissolution, the gadolinium fluoride precipitation operation is carried out with the subsequent extraction purification of the obtained uranyl nitrate solutions. At the deposition stage, almost all the gadolinium contained in the scraps is transferred to the GdF3 precipitate and sent to the tailings dump as part of the solid waste. In order to determine the possibility of obtaining gadolinium oxide from waste processing of uran-gadolinium containing materials, exploratory studies were initiated. In the course of the work, various methods of obtaining gadolinium oxide were tested. A number of experiments were carried out to refine the modes of obtaining gadolinium oxide by the method of two-stage precipitation of oxalate. A technological scheme was developed, according to which a finished product was obtained, suitable for further use in the technology of obtaining uranium-gadolinium tablets of UMP JSC. The scheme consists of the following main operations: dissolution of gadolinium fluoride in a solution of aluminum nitrate, precipitation of gadolinium oxalate, washing of gadolinium oxalate in the first stage of precipitation with a solution of nitric acid, conversion of oxalate to gadolinium hydroxide, dissolution of hydroxide in a solution of nitric acid, re-precipitation of gadolinium oxalate, calcination to gadolinium oxide.
Abstract: One of the activities of the Uranium production of JSC "UMP" is the processing of hard-to-open uranium-gadolinium-containing scraps. When processing materials of this type, after their dissolution, the gadolinium fluoride precipitation operation is carried out with the subsequent extraction purification of the obtained uranyl nitrate solutions. At ...
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Laser Duration of Surface Textures of Slab Design
Issue:
Volume 6, Issue 4, December 2021
Pages:
84-86
Received:
18 September 2021
Accepted:
12 October 2021
Published:
9 December 2021
Abstract: The laser has a precise directional motion on products. This is used to develop a surface texture on a slab geometry. This is used in most products for different requirements. This can include designs such as stability, tensile, compressive and flexural resistances of slabs. These contain various products. This can require a replacement or reusability without developing more products. The surface textures can be developed on a product at different positions and dimensions. This engages with the surface without the corrosion of the product. To ensure a much higher uses for suppliers and producers. These slabs can be linear or nonlinear. This depends on the contacting surfaces of the products. The surface texture prevents the materials degradation for certain uses. The material content is unchanged when to be used. The laser is a high precision method to develop surface textures of various dimensions. This laser is in the direction of the geometry design. To produce a change of the surface. The laser beam density was varied at the the product. This produced a change in the tensile, compressive and rotational properties of the geometry.
Abstract: The laser has a precise directional motion on products. This is used to develop a surface texture on a slab geometry. This is used in most products for different requirements. This can include designs such as stability, tensile, compressive and flexural resistances of slabs. These contain various products. This can require a replacement or reusabil...
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