Nitrik Asit Özütlemesi İle Doğal Manyezit Cevherinden Magnezyumun Çözünmesi

Yıl 2012, Cilt: 25 Sayı: 2, 43 - 56, 31.12.2012

T. Ennil Köse

Öz

Manyezit (MgCO3) tuz tipi bir
mineral olup Türkiye’de bol miktarda bulunur. Bu çalışmada manyezitin nitrik
asit çözeltisi içindeki çözünürlüğü araştırılmıştır. Özütleme prosesi üzerine
partikül boyutu, tepkime sıcaklığı, katı-sıvı oranı ve asit derişimi gibi
parametrelerin etkileri incelenmiştir. Manyezit cevherinin çözünme hızının,
tepkime sıcaklığı ve asit derişiminin artmasıyla ve katı-sıvı oranının
azalmasıyla arttığı görülmüştür. Partikül boyutunun ise çözünme hızına önemli
bir etkisi olmamıştır. Deneysel veriler kinetiğin, küçülen hacim modeline
uyduğunu göstermiştir. Özütleme prosesinin aktivasyon enerjisi 3.24 kJ/mol
olarak hesaplanmıştır.

Anahtar Kelimeler

Manyezit; Nitrik asit; Çözünme; Özütleme; Kinetik

Dıssolutıon Of Magnesıum From Natural Magnesıte Ore By Nıtrıc Acıd Leachıng

Öz

Magnesite (MgCO3) is a salt-type
mineral and is found in large amounts in Turkey. In this study, dissolution of
magnesite in nitric acid solutions was investigated. The effects of various
parameters such as particle size, reaction temperature, solid to liquid ratio
and acid concentration on the leaching process were examined. It was determined
that the dissolution rate of magnesite increased with increasing reaction
temperature and acid concentration, and decreasing solid to liquid ratio. No significant
effect of particle size was observed on the dissolution of magnesium. The
experimental data fitted the shrinking core model. The activation energy of the
leaching process was calculated as 3.24 kJ/mol

Anahtar Kelimeler

Magnesite; Nitric acid; Dissolution; Leaching; Kinetics.

Kaynakça

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