Document Type : Original Research Paper

Authors

1 Sistan & Baluchestan University, Faculty of Chemical Engineering, Zahedan, Iran

2 Islamic Azad University, Basic Science Faculty, Department of Geology, Zahedan Branch, Zahedan, Iran

Abstract

       The effect of temperature, mixer ratio and acid thickness on the rate of magnesite dissolution in nitric acid was investigated in this laboratory research.
The result shows dissolution rate increases with rising temperature when the size of particles is reduced. At the beginning of the reaction, thicker acid increases the rate of dissolution but as the acid grows thicker not only there is no overwhelming changes obvious but also extends the duration due to product layer formed on the mineral grain surface during the reaction. This has less effect on thinner acid and smaller particles.
The kinetic results shows that magnesite minerals dissolution in nitric acid follows the kinetic model , Optimized laboratory conditions are a temperature of 30 oC, nitric acid thickness of 50 %, size of particles: 250-297   ., mixer ratio of 300 rounds per min. and reaction duration of 170 min.
 

Keywords

References
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