PECULIARITIES OF CATHODIC REDUCTION OF RHENIUM(VII) IN ALKALINE ELECTROLYTES
Relevance. Rhenium and its alloys are refractory, heat-resistant, high-temperature, and corrosion-resistant materials which are used in aircraft and rocket engineering, electrical engineering, in production of catalysts. Rhenium belongs to rare elements, this necessitates the improvement of technolo...
| Main Authors: | , , |
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| Format: | Article |
| Language: | Russian |
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Tomsk Polytechnic University
2019-03-01
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| Series: | Известия Томского политехнического университета: Инжиниринг георесурсов |
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| Online Access: | http://izvestiya.tpu.ru/archive/article/view/175/73 |
| _version_ | 1818150797767081984 |
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| author | Svetlana V. Kovaleva Irina A. Shabanova Andrey V. Korshunov |
| author_facet | Svetlana V. Kovaleva Irina A. Shabanova Andrey V. Korshunov |
| author_sort | Svetlana V. Kovaleva |
| collection | DOAJ |
| description | Relevance. Rhenium and its alloys are refractory, heat-resistant, high-temperature, and corrosion-resistant materials which are used in aircraft and rocket engineering, electrical engineering, in production of catalysts. Rhenium belongs to rare elements, this necessitates the improvement of technological processes for its extraction from natural raw materials and waste materials, as well as improving the accuracy of analytical methods for its determination. Electrochemical methods are optimal in terms of cost, expressiveness and availability for analysis and processing of rhenium-containing raw materials. In this regard, the study of the regularities of the electrode processes involving rhenium and its compounds is relevant. The aim of the research is to establish the sequence of cathodic reduction of perrhenate ions in alkaline electrolytes. Objects: ammonium perrhenate solutions, sodium hydroxide solutions. Methods: direct and alternating current polarography, cyclic voltammetry, accumulative potentiostatic electrolysis. Results. The authors have determined the interval of potentials of cathodic reduction of ReO4– ions (1×10–5…1×10–2 М) in alkaline medium (1...10 M NaOH) at mercury electrodes is –1,25…–1,75 V (sat. Ag/AgCl/KCl). A significant contribution of catalytic and adsorption current components to the total value of cathodic current was established on the basis of temperature dependence of limiting current and current dependence on height of dropping Hg-electrode column. A sequence for reduction of ReO4– in alkaline electrolytes was established using cyclic voltammetry, and a scheme of the cathodic process was proposed which includes electrode, chemical and adsorption stages. Experimental data on potentiostatic electrolysis and on voltammetry of chemically synthesized ReO2 were used to interpret the polarographic results. The paper demonstrates the importance of the obtained results for analytical determination of rhenium. |
| first_indexed | 2024-12-11T13:28:39Z |
| format | Article |
| id | doaj.art-7e1d810e7ea44d5bb307f4116816a525 |
| institution | Directory Open Access Journal |
| issn | 2500-1019 2413-1830 |
| language | Russian |
| last_indexed | 2024-12-11T13:28:39Z |
| publishDate | 2019-03-01 |
| publisher | Tomsk Polytechnic University |
| record_format | Article |
| series | Известия Томского политехнического университета: Инжиниринг георесурсов |
| spelling | doaj.art-7e1d810e7ea44d5bb307f4116816a5252022-12-22T01:05:24ZrusTomsk Polytechnic UniversityИзвестия Томского политехнического университета: Инжиниринг георесурсов2500-10192413-18302019-03-01330316317410.18799/24131830/2019/3/175PECULIARITIES OF CATHODIC REDUCTION OF RHENIUM(VII) IN ALKALINE ELECTROLYTESSvetlana V. Kovaleva0Irina A. Shabanova1Andrey V. Korshunov2Tomsk State Pedagogical UniversityTomsk State Pedagogical UniversityNational Research Tomsk Polytechnic UniversityRelevance. Rhenium and its alloys are refractory, heat-resistant, high-temperature, and corrosion-resistant materials which are used in aircraft and rocket engineering, electrical engineering, in production of catalysts. Rhenium belongs to rare elements, this necessitates the improvement of technological processes for its extraction from natural raw materials and waste materials, as well as improving the accuracy of analytical methods for its determination. Electrochemical methods are optimal in terms of cost, expressiveness and availability for analysis and processing of rhenium-containing raw materials. In this regard, the study of the regularities of the electrode processes involving rhenium and its compounds is relevant. The aim of the research is to establish the sequence of cathodic reduction of perrhenate ions in alkaline electrolytes. Objects: ammonium perrhenate solutions, sodium hydroxide solutions. Methods: direct and alternating current polarography, cyclic voltammetry, accumulative potentiostatic electrolysis. Results. The authors have determined the interval of potentials of cathodic reduction of ReO4– ions (1×10–5…1×10–2 М) in alkaline medium (1...10 M NaOH) at mercury electrodes is –1,25…–1,75 V (sat. Ag/AgCl/KCl). A significant contribution of catalytic and adsorption current components to the total value of cathodic current was established on the basis of temperature dependence of limiting current and current dependence on height of dropping Hg-electrode column. A sequence for reduction of ReO4– in alkaline electrolytes was established using cyclic voltammetry, and a scheme of the cathodic process was proposed which includes electrode, chemical and adsorption stages. Experimental data on potentiostatic electrolysis and on voltammetry of chemically synthesized ReO2 were used to interpret the polarographic results. The paper demonstrates the importance of the obtained results for analytical determination of rhenium.http://izvestiya.tpu.ru/archive/article/view/175/73perrhenate ionsalkaline electrolytespolarographycyclic voltammetrymercury electrodecathodic process |
| spellingShingle | Svetlana V. Kovaleva Irina A. Shabanova Andrey V. Korshunov PECULIARITIES OF CATHODIC REDUCTION OF RHENIUM(VII) IN ALKALINE ELECTROLYTES Известия Томского политехнического университета: Инжиниринг георесурсов perrhenate ions alkaline electrolytes polarography cyclic voltammetry mercury electrode cathodic process |
| title | PECULIARITIES OF CATHODIC REDUCTION OF RHENIUM(VII) IN ALKALINE ELECTROLYTES |
| title_full | PECULIARITIES OF CATHODIC REDUCTION OF RHENIUM(VII) IN ALKALINE ELECTROLYTES |
| title_fullStr | PECULIARITIES OF CATHODIC REDUCTION OF RHENIUM(VII) IN ALKALINE ELECTROLYTES |
| title_full_unstemmed | PECULIARITIES OF CATHODIC REDUCTION OF RHENIUM(VII) IN ALKALINE ELECTROLYTES |
| title_short | PECULIARITIES OF CATHODIC REDUCTION OF RHENIUM(VII) IN ALKALINE ELECTROLYTES |
| title_sort | peculiarities of cathodic reduction of rhenium vii in alkaline electrolytes |
| topic | perrhenate ions alkaline electrolytes polarography cyclic voltammetry mercury electrode cathodic process |
| url | http://izvestiya.tpu.ru/archive/article/view/175/73 |
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