Investigation of Magnesium Production from Magnesium Oxide and Dolomite Reduced by Aluminum, Ferrosilicon, and Calcium Carbide

Abstract

In this study, metallic magnesium was produced using the Magnetherm process with different magnesium sources and various reducing agents. Magnesium oxide (MgO) and dolomite (CaO·MgO) were used as magnesium sources, while aluminum chips (Al), ferrosilicon (FeSi), and calcium carbide (CaC2) served as reducing agents. The effects of using different magnesium sources and reductants under identical experimental parameters on both reduction efficiency and recovery yield were investigated. The experiments were carried out for 1.5 minutes at a current of 600 A in the Al- CaO·MgO, FeSi-MgO, FeSi-CaO·MgO, CaC2-MgO, and CaC2-CaO·MgO systems. Thermodynamic modeling was performed using the FactSage software, and the results were compared with experimental findings. The produced magnesium was obtained in powder form, and various analyses were performed on both magnesium powders and slags. XRD and carbon determination tests were applied to the magnesium powders and slags; atomic absorption spectroscopy (AAS) was used for the magnesium powders; and XRF analysis was conducted on the slags. According to the experimental results, the highest reduction efficiency was obtained in the FeSi-CaO·MgO system with 98.17%, while the highest recovery yield was achieved in the Al- CaO·MgO system with 93.75%.

Keywords

• Magnetherm
• Reduction
• Magnesium Production

Alüminyum, Ferrosilisyum ve Kalsiyum Karbür ile Magnezyum Oksit ve Dolomitin Redüksiyonunda Magnezyum Üretiminin İncelenmesi

Abstract

Bu çalışmada, Magnetherm prosesi ile farklı magnezyum kaynakları ve farklı redükleyicilerle metalik magnezyum üretimi gerçekleştirilmiştir. Magnezyum kaynağı olarak magnezyum oksit (MgO) ve dolomit (CaO·MgO); redükleyici ajan olarak alüminyum talaşları (Al), ferosilisyum (FeSi) ve kalsiyum karbür (CaC2) kullanılmıştır. Bu çalışmada aynı deney parametrelerinde farklı magnezyum kaynağı kullanarak farklı redükleyici kullanımının redüksiyon verimi ve geri kazanım verimi üzerindeki etkisi araştırılmıştır. Deneyler, 1,5 dakikalık deney süresi ve 600 amperlik akım değerinde, Al- CaO·MgO, FeSi-MgO, FeSi-CaO·MgO, CaC2-MgO ve CaC2-CaO·MgO sistemlerinde gerçekleştirilmiştir. FactSage programı kullanılarak termodinamik modelleme yapılmış ve sonuçlar deneysel bulgularla karşılaştırılmıştır. Üretilen magnezyumlar toz formunda elde edilmiş ve magnezyum tozları ile cüruflara çeşitli analizler uygulanmıştır. Magnezyum tozları ve cüruflara XRD ve karbon tayini; magnezyum tozlarına atomik absorbsiyon analizi (AAS); cüruflara ise XRF analizi yapılmıştır. Deney sonuçlarına göre, en yüksek redüksiyon verimi %98,17 ile FeSi-CaO·MgO redüksiyonunda, en yüksek geri kazanım verimi ise %93,75 ile Al- CaO·MgO redüksiyonunda elde edilmiştir.

Keywords

• Magnetherm Proses
• Redüksiyon
• Magnezyum Üretimi

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