Oxygen Transfer Ability of Co-Pb Metal Oxides during the Chemical Looping Oxidation of Tuncbilek Lignite

Öz

The study aims to determine the oxygen transfer ability of cobalt lead (Co-Pb) individual and mixed oxides during the thermal decomposition of Tuncbilek lignite under inert atmosphere. Thermodynamic calculations of reduction reactions were performed to show the favorable reduction temperatures for the different reductive gases. Co and Pb mixed metal oxides were prepared by wet impregnation method and they characterized by X-ray diffractometer and Raman spectroscopy. Oxygen transfer performances of these oxides were evaluated by thermal gravimetric analysis (TGA) in terms of oxidation rates of lignite sample under N2 flows in the range of temperatures between 40 to 600ºC. The results of thermal gravimetric analysis (TGA) indicated that the optimum coal to Co-Pb metal oxides ratio based on oxidation efficiency was 0.11.

Anahtar Kelimeler

• Chemical looping oxidation

Oxygen Transfer Ability of Co-Pb Metal Oxides during the Chemical Looping Oxidation of Tuncbilek Lignite

Öz

Bu çalışma, kobalt-kurşun (Co-Pb) karışık metal oksitlerin Tuncbilek linyitlerininin inert ortamda termal bozunması esnasında göstermiş oldukları oksijen transfer yeteneğini belirlemeyi amaçlamaktadır. Bu metal oksitlerin farklı indirgeyici gazlar varlığında indirgenme reaksiyonlarının termodinamik hesaplamaları uygun reaksiyon sıcaklıklarını belirlemek için yapılmıştır. Co-Pb karışık metal oksitler ıslak emdirme yöntemiyle hazırlanmış ve X-ray kırınımı ve Raman spektrometresi ile karakterize edilmiştir. Bu metal oksitlerin oksijen transfer performansları termal gravimetrik analiz (TGA) metoduyla 40-600ºC sıcaklık aralığında azot atmosferinde gerçekleştirilmiştir. TGA sonuçları, oksidasyon etkinliğine dayalı optimum linyit/ Co-Pb mixed oxide oranının 0.11 olduğunu ortaya koymuştur.

Anahtar Kelimeler

• Chemical looping oxidation

Kaynakça

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