MAGNESIUM, TITANIUM, RARE METALS, SEMICONDUCTORS | |
ArticleName | Large-scale testings of vacuum-distillation refining of ill-conditioned rough selenium |
ArticleAuthor | Khrapunov E. V., Trebukhov S. A., Marki I. A., Adylkanova M. A., Kaldybekov F. Kh. |
ArticleAuthorData | “Center of Sciences about Earth, Metallurgy and Concentration” JSC, Almaty, Republic of Kazakhstan: E. V. Khrapunov, Professor, Chief Researcher, e-mail: imarki@mail.ru F. Kh. Kaldybekov, Engineer
D. Serikbayev East Kazakhstan State Technical University, Ust-Kamenogorsk, Republic of Kazakhstan: |
Abstract | This paper contents the results of integrated testings of obtaining of the grade composition metals from ill-conditioned rough selenium by vacuum distillation method. This method is usually applied during the purification of technical grade selenium from impurities. Ill-conditioned rough selenium is formed during the processing of anode sludges of copper electrolytic refining in the Kaldo furnace. As a result of the testings, there were processed 342.55 kg of illconditioned rough selenium with the humidity of 18.78% (278.22 kg in dry weight), containing 82.4% of the main component. After the receiving fusion, extraction of fused metal, containing 95.12% of the main component, was 70.5% (81.4% of selenium extraction). The extraction of slags was 18.7%. The content of selenium in slag has averaged by 63.95%. During the vacuum distillation refining of the fused selenium, there were produced 1.1 kg of the solid residue and 1805.05 kg of the refined selenium. The refined selenium contained more than 99.6% of the main component and corresponded to the CT1 (ST1) grade metal, which is stated for the export (State Standard 10298–79). The concentration of silver in the solid residue, in comparison with its content in initial materials, is increased to more than 30 times. At the same time, the concentration of gold is increased to 10 times. For the purpose of definition of possibility of increasing of selenium extraction, the receiving fusion slags were also exposed to the distillation at a higher temperature (500–550 oC). At the same time, there were additionally obtained 29.95 kg of selenium, containing 99.15% of Se, which does not correspond to the grade metal, according to the content of impurities. In spite of increasing of the throughout extraction of selenium during the distillation of slags by more than 12% (from 80.42 to 93.37%), the selenium, obtained from slags, requires the additional operation of purification from the impurities for the purpose of its final processing to the grade composition selenium. That's why, it is the most reasonable to return the slags (with output of lesser than 20%), obtained after the receiving fusion, to the Kaldo furnace, for the purpose of ensuring of more stable operation of vacuum equipment and reduction of losses of selenium and noble metals with the whole range of middlings, obtained from the ill-conditioned rough selenium (secondary sublimates and residues). It is noted that the processing of high-humid and acidity rough selenium is not reasonable, because of the extremely campaign equipment reduction. In connection with this, it is recommended to conduct through the pre-washed rough selenium and its drying. The test results demonstrate the possibility of efficient illconditioned rough selenium concentration to produce the grade composition metal by the vacuum distillation method. |
keywords | Selenium, refining, distillation, filtration, vacuum, melt, receiving fusion, evaporator, condenser |
References | 1. Chernyshev A. A., Petrov G. V., Belenkiy A. M., Kovalev V. N., Kukolevskiy A. S. Metallurg — Metallurgist. 2009. No. 5. pp. 54–56. 4. Yukhtanov D. M., Pletneva N. V. Zhurnal prikladnoy khimii — Russian Journal of Applied Chemistry. 1960. Vol. 33, Iss. 9. p. 1951. |
Language of full-text | russian |
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