Molybdenum Production by the Electrochemical Reduction of Solid Molybdenum Compounds

Year 2017, Volume: 32 Issue: 2, 207 - 214, 15.06.2017

Metehan Erdoğan Bengisu Akpınar İshak Karakaya

https://doi.org/10.21605/cukurovaummfd.358425

Abstract

The electrochemical reduction of molybdenum compounds; CaMoO4 and MoS2, which form the cathode
of the cell by being attached to a current collector, was investigated. Molten CaCl2-NaCl salt solutions
were used as the electrolyte. The compositions and morphologies of the reduced samples were determined
by X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses. The examinations showed
that it is not possible to produce Mo without loss by the electrochemical reduction of CaMoO4. The
aforementioned compound has around 1.9% solubility in eutectic CaCl2-NaCl salt solution at 750oC.
Formation of Mo was not observed at 600oC where the solubility was relatively not important. On the
other hand, production of molybdenum from MoS2, which is the most important Mo mineral found in
nature, was accomplished successfully. Pure molybdenum powder was obtained by the dissolution of
calcium products found in the reduced samples in dilute acid solution.

Keywords

: Electrochemical reduction, Electrodeoxidation, Mo, CaMoO4, MoS2

Katı Molibden Bileşiklerinin Elektrokimyasal İndirgenmesiyle Molibden Üretimi

Abstract

İletken bir telin ucuna tutturulmak suretiyle hücrenin katodunu oluşturan, molibden bileşikleri; CaMoO4 ve MoS2’nin elektrokimyasal yöntemlerle indirgenmesi incelenmiştir. Elektrolit olarak, erimiş haldeki CaCl2-NaCl tuz çözeltileri kullanılmıştır. İndirgenen örneklerin içeriği ve morfolojisi X-ışınları kırınımı (XRD) ve taramalı elektron mikroskobu (SEM) analizleri aracılığıyla belirlenmiştir. Yapılan incelemeler CaMoO4’ten elektrokimyasal indirgeme yöntemiyle kayıp vermeksizin Mo üretmenin mümkün olmadığını göstermiştir. Söz konusu bileşik ötektik CaCl2-NaCl çözeltisi içerisinde 750oC’de yaklaşık %1,9 civarında çözünürlüğe sahiptir. Çözünürlüğün nispeten önemsiz olduğu 600oC’de ise Mo oluĢumu gözlemlenmemiştir. Molibdenin doğadaki en önemli minerali olan MoS2’den elektrokimyasal indirgeme yöntemiyle Mo üretimi ise 750 oC’de başarıyla gerçekleştirilmiştir. İndirgenen numunedeki kalsiyum bileşiklerinin seyreltik asit çözeltisinde çözündürülmesi ile saf Mo tozu elde edilmiştir.  

Keywords

Elektrokimyasal indirgeme, Elektrodeoksidasyon, Mo, CaMoO4, MoS2

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