Salih AYDOĞAN, ALİ ARAS, Mehmet CANBAZOĞLU

Oxidative ammonia leaching of sphalerite concentrate

Bu makalede, sfalerit konsantresinin amonyak çözeltisinde liç kinetiğine ait bir çalışma sunulmuştur. Amonyak konsantrasyonunun, oksijen kısmi basıncının, reaksiyon sıcaklığının ve tane boyutunun liç hızına etkisi araştırılmıştır. Deneylerden elde edilen sonuçlara küçülen partikül modeli uygulanmıştır. Oksijen kısmi basıncına $PO_2$ (1-10 atm) ve $NH_3$ konsantrasyonuna (1.05-5.20 M) göre reaksiyon dereceleri sırasıyla 0.22 ve 0.63 olarak bulunmuştur. 90-130 °C aralığında aktivasyon enerjisinin 43.59 kj/mol olduğu belirlenmiştir. Görünür hız sabitinin ortalama başlangıç tane yarıçapı ile ters ilişkili olduğu görülmüştür. Bu çalışmadan elde edilen sonuçlar sfalerit liçinin reaksiyon kontrollü bir proses olduğunu göstermiştir.

Sfalerit konsantresinin oksitleyici amonyak liçi

This paper presents a study of kinetics of leaching of sphalerite concentrate in ammonia solutions. The effects of ammonia concentration, oxygen partial pressure, reaction temperature and particle size on the leaching rate were investigated. The shrinking core model was applied to the results obtained from these experiments. Reaction order with respect to $PO_2$ (1-10 atm.) and $NH_3$ concentration (1.05-5.20 M) were 0.22 and 0.63 and the activation energy was determined to be 43.59 kj/mol in the temperature range of 90-130 °C. In addition, the apparent rate constant is in inverse relationship with the mean initial particle radius. The results of this study showed that the leaching of sphalerite was a reaction controlled process.

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