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Date submitted2024-04-10
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Date accepted2024-06-03
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Date published2024-07-19
Combined method for processing spent acid etching solution obtained during manufacturing of titanium products
Possessing high strength, low density and significant chemical resistance, titanium has found wide application in various fields of the national economy – the chemical industry, aviation and rocket technology, mechanical engineering, medicine, etc. The production of titanium products is hampered by a fairly strong oxide film covering its surface. Removal of the oxide film from the surface of titanium workpieces is carried out by etching in solutions of mineral acids of various compositions. A spent acid etching solution (SAES) is formed, containing titanium salt and the remainder of unreacted acids. Almost all etching solutions contain HF and one of the strong acids. This is H2SO4, HCl or HNO3. Thus, the SAES includes ions of titanium, fluorine or chlorine, orsulfate, or nitrate. SAES is quite toxic and must be diluted or cleaned several times before being discharged into a reservoir. Most of the methods used to extract impurities contained in SAES lead to a decrease in their content. As a result of such purification, there is a loss of substances contained in SAES in significant quantities and of interest for further use. The work presents experimental results obtained from the combined processing of SAES containing titanium fluoride, hydrofluoric and hydrochloric acids. At the first stage, SAES is treated with sodium hydroxide. The resulting titanium hydroxide precipitate is filtered off. At the second stage, the filtrate containing sodium fluoride and chloride is processed in a membrane electrolyzer. In this case, not only the extraction of sodium salts from the filtrate occurs, but also the production of sodium hydroxide and a mixture of hydrofluoric and hydrochloric acids. Sodium hydroxide can be used for processing SAES, and a mixture of acids for etching titanium workpieces.
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Date submitted2021-03-12
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Date accepted2021-04-12
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Date published2021-06-24
Increasing the efficiency of phosphate ore processing using flotation method
The paper presents flotation of two phosphate ore samples of different origin. Statistical analysis was used to study the effect of operating parameters on flotation efficiency. The paper proposes to increase the efficiency of flotation processing of magmatic phosphate ore with a low grade of the valuable component (P 2 O 5 = 10.88 %), containing nepheline and feldspars, by means of direct anionic flotation. Authors present an optimization of anionic flotation using tall oil fatty acids mixed with anionic phospholane as an anionic collector. The effect of adding soda ash to compensate for the influence of calcium cations on technological parameters of P 2 O 5 flotation was examined. The results of studying the flotation of nepheline ore (flotation tailings of magmatic phosphate ore) showed that replacement of phospholane with oxyethylated isotridecanol allowed to obtain a high-quality concentrate. It was estimated that with the addition of Na 2 CO 3 in the amount of 2,000 g/t, a concentrate was obtained with the grade and recovery of phosphorus pentoxide equal to 39.15 and 94.19 %, respectively. The paper proposes to increase the efficiency of flotation processing of sedimentary phosphate ore with a low grade of the valuable component (P 2 O 5 = 22.5 %), containing gypsum and quartz, by means of desliming followed by anionic or cationic reverse flotation. Tall oil fatty acid with anionic phospholane was used as a collector in anionic reverse flotation, and amine was used in cationic reverse flotation. Sodium tripolyphosphate was used as a P 2 O 5 depressant. It was found to be an effective depressant in both anionic and cationic flotation. When analyzing the statistical plan, it was estimated that the maximum grade of the valuable component in the concentrate (P 2 O 5 = 31.23 %) and the recovery to concentrate of 95.22 % were obtained in the chamber product at amine consumption of 950.88 g/t and sodium tripolyphosphate consumption of 500 g/t.
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Date submitted2015-10-17
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Date accepted2015-12-19
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Date published2016-08-22
Improving the retention of minerals in the course of separating monolith from bedrock with the use of gas generator cartridges
- Authors:
- G. P. Paramonov
- V. N. Kovalevskii
- Peter Mozer
Results are presented on the effect of firing rate on pressure pulse in charge camera and fracture stress during spalling. Results are presented of comparative calculations using the equations of autocatalytic reactions of firing rates and escape of reaction products for the system of sodium chlorate - polythene (propylene) in pipe shape. Dependences are obtained of firing rate on concentration of gas generating mixture, its density, components size distribution and cartridge case size. Experimental and computational data were used to consider the conditions of firing turning into explosion for compositions based on sodium chlorate and hydrocarbons in layered and powdered systems. The relation is retrieved between the technological parameters of mining activities (blast hole to blast hole distance, blast hole diameter, depth of cartridge placement) and specific cartridge consumption along the spalling line with gas generators going off.
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Date submitted2014-11-01
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Date accepted2015-01-02
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Date published2015-10-26
Development of an environmentally safe gold extraction method from refractory ores using sodium thiosulfate as an extractant
- Authors:
- Yu. V. Sharikov
- Ilkka Turunen
The article presents the results of a mathematical model development for the process of gold leaching from gold-containing ores and concentrates. A mathematical model has been developed by analyzing the chemistry of reactions and mass transfer processes. On the base of a kinetic extraction model and a hydrodynamic complete mixing model a mathematical model of thiosulfate leaching process in various types batch reactors, complete mixing flow process vessels and complete mixing reactor columns with different numbers of vessels in a column has been developed. The effect of the number of reactors in a column has been investigated and optimal segmentation conditions have been found. Based on the investigation of the process using the mathematical model a control system structure has been designed to provide maximum conversion at the exit area of a reactor column.
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Date submitted2009-08-06
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Date accepted2009-10-10
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Date published2010-02-01
Allocation of tellurium from difficult on structure of sulfuric acid solutions
- Authors:
- S. B. Fokina
As the main source of reception of tellurium serve electrolytic copper refinery slimes. In the conditions of manufacture expansion and transition on technology decopperizing slimes by pressure leaching O 2 -H 2 SO 4 media, the solution (decopperized product) becomes the basic concentrator of tellurium. Extraction of tellurium from a decopperized (pressure-leached) liquid products is considered. The method allows to raise percent of extraction of tellurium from initial raw materials and to enrich pressure-leached solid product with precious metals.