Production of Aluminum Titanate from Pyrophyllite Ore

Öz

Aluminum titanate (Al2TiO5) is an advanced ceramic material produced artificially from the alumina (Al2O3) and titanium oxide (TiO2) components. In this study, alumina which is produced from pyrophyllite ore and commercial rutile were used to manufacture the aluminum titanate. The alumina used in the study was obtained by roasting the aluminum chloride salt precipitated from the loaded solution obtained by HCl leaching of the pyrophyllite ore. The resulting alumina and commercial rutile mixture is intensively milled, shaped and sintered at different temperatures to produce aluminum titanate. The result of sintering is that aluminum titanate formation is at 1359 °C in the milled mixture and at 1367 °C in the unmilled mixture. Formation of aluminum titanate at a lower temperature than the unmilled mixture, much less presence of microcracks and lack of pores clearly demonstrate the effect of mechanical activation. As a result, it has been shown that aluminum titanate with high added value can be produced from alumina recovered from pyrophyllite ore by hydrometallurgical processes.

Anahtar Kelimeler

• pyrophyllite
• alumina
• mechanical activation
• aluminum titanate

Pirofillit Cevherinden Alüminyum Titanat Üretimi

Öz

Alüminyum titanat (Al2TiO5), alümina (Al2O3) ve titanyum oksit (TiO2) bileşenlerinden yapay olarak üretilen ileri seramik bir malzemedir. Bu çalışmada alüminyum titanat üretmek için pirofillit cevherinden üretilen alümina ve ticari rutil kullanılmıştır. Çalışmada kullanılan alümina, pirofillit cevherinin HCl liçi ile elde edilen yüklü çözeltiden çöktürülen alüminyum klorür tuzunun kavrulması sonucu elde edilmiştir. Elde edilen alümina ve ticari rutil karışımı alüminyum titanat üretmek amacıyla aşırı öğütülmüş, şekillendirilmiş ve farklı sıcaklıklarda sinterlenmiştir. Sinterleme sonucu alüminyum titanat oluşumu öğütülmüş karışımda 1359 °C iken öğütülmemiş karışımda 1367 °C’dir. Aşırı öğütülmüş karışımdan daha düşük sıcaklıkta alüminyum titanat oluşması, mikroçatlak ve gözenekliliğin daha az olması mekanik aktivasyonun etkisini açıkça göstermektedir. Sonuç olarak pirofillit cevherinden hidrometalurjik süreçlerle kazanılan alüminadan, katma değeri daha yüksek olan alüminyum titanat üretilebileceği belirlenmiştir.

Anahtar Kelimeler

• Pirofillit
• alümina
• mekanik aktivasyon
• alüminyum titanat

Kaynakça

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