Currently, the main raw materials sources of platinum group metals in Russia are complex sulfide copper-nickel ores of the Taimyr region and placer deposits. However, in view of the inevitable loss of platinum metals during the metallurgical processing of initial ores and the deterioration of the quality of ore raw materials, along with a decrease in the share of platinum mining from placers, there is a need to look for new non-traditional sources of platinum group metals. Dunnites of the Middle Urals are promising platinum-bearing raw materials. The use of the gravitational-magnetic processing of chromium ores of dunnite deposits makes it possible to identify a magnetic platinum-bearing concentrate with a high content of magnetite and platinum-iron alloys, they can be refined using chemical-metallurgical methods. This article presents the results of research of identifying peculiarities of technological behavior of chromium, iron and noble metals during mechanical processing of ledge chromium ore. The kinetic regularities of the sulfuric acid decomposition of magnetite are determined. Optimum technological parameters of sulfuric acid leaching of iron from magnetic products of chromium ore dressing are established. Based on the conducted studies, the PDF and PID for the complex processing of chromium ores of dunnite deposits is proposed, which ensures the production of a rich platinum-bearing concentrate and a high-quality chromite concentrate that meets the requirements of chemical production.
The main source of selenium is copper anode slime. But during the pyrometallurgical treatment of sulphide polymetallic ores significant amount of selenium along with radiogenic osmium and rhenium is concentrated in the solid-phase products of acid wash extraction and cannot be extracted, as gets lost with discharged chromium-containing solutions of osmium stage. The paper presents results of research into selenium reduction in the chromium-containing sulfuric acid medium by sulfurous gas and sodium sulphite. The use of the above reducers in optimum conditions leads to almost complete recovery of selenium (VI) while selenium (IV) extraction rate is not exceeding 60 %. The chrome (III) present in solutions has no impact on the selenium extraction rate. Chrome (VI) is almost completely reduced to a trivalent state, thus its negative impact on subsequent rhenium sorption from solutions purified from selenium is excluded. In view of a high rate of selenium extraction from chromium-containing sulfuric acid solutions formed in the process of radiogenic osmium production using sulfurous gas and sodium sulphite, choice of a method for selenium reduction is to a great extent dependent on the company’s profile.
Incidental concentrating of valuable elements in processing sulphide-copper ores yields supplementary semi-products enriched with osmium, rhenium, and selenium. Peculiar features of processing properties of rhenium, radiogenic osmium, and selenium are shown in this paper, as well as concentrators for rare microelements and ways of their extraction.
Dump slag dust products of man-made deposits of Norilsk region are a promising source of precious metals. Methods for concentrating precious and base metals in sediment cores of multiponds slag products are studied.
The results of studies on sulphatization refinement of mattes, containing platinum metals, it. The perspective of technology concentration of platinum metals from the products of processing man-made waste on a scheme «smelting matte – sulphatization» are justify.
Shows the shortcomings of traditional roasting-selenide technology of extraction of selenium. The results of studies on the development of reagentless electrochemical method of removing it. A basic technological scheme of obtaining technical selenium in terms of electroextraction was offer.
A thermodynamic analysis of the system Se – H 2 O was prospect. Plotted dependences the concentrations of selenium oxyanions from the pH of the solution and polarization graphs for various materials of the anode. Draw conclusions about the regularities of selenium electroextraction from selenium solutions.
The results of studies on the intensification of the process of sorption extraction of iridium with highly basic anion exchanger AMP from sulfate solutions has been done. The effect of oxidant on the parameters of sorption of iridium has been described. Dependence of extraction of iridium in the sorbent from the temperature of the process and flowing anionite has been established. The perspective of the method of anionite sorption of platinum metals with highly basic sorbent AMP has been proved.
The processes occurring at nitric acid leaching of copper-electrolyte slimes are described. The influence of firing temperature and concentration of nitric acid on the degree of transition of silver and related elements into solution is investigated. Optimal modes providing high extraction of silver into solution and concentration of gold in the insoluble residue have been established.
Methods of refining of tellurium of technical purity have been developed and introduced. Due to application of oxidative smelting and distillation industrial batches of tellurium were obtained, in which the content of guest impurities meets semiconductor grades.
The behavior of silver selenide in the whole range of pH values has been studied using thermodynamic calculations and polarization measurements. Pourbae diagrams at temperatures of 25 and 80°C have been constructed. The forms of selenium in acidic and alkaline solutions were determined.
This type of deposits is the main exploration target for Pt, Ir, Os, Ru. Inferred resources of platinum group elements (PGM) from Ray-Iz are estimated at several tons. Methods of separation of rich concentrates of platinum metals by mechanical enrichment have been studied. Hydrometallurgical technology of PGM concentrates extraction from chromite ores is recommended. The expediency of PGM precipitation during processing of chromite materials at chemical plants even at low PGM content is shown. The prospectivity of chromite ores of the Polar Urals as a source of PGMs is substantiated.