NAOH Leaching Study

  • Akshoy Kumar Chakraborty


It was thought earlier that kaolinite decomposes during formation of metakaolinite into free silica and alumina. Some also believed that metakaolinite transforms to spinel phase with the liberation of SiO2. Further, the amount of SiO2 exolvation indirectly predicts the nature of spinel phase formed i.e., whether it is γ-Al2O3 or Al–Si spinel. Since the composition of γ-Al2O3 and proposed Al–Si spinel is different. So it is obvious that the amount of amorphous SiO2 would be different. Thus, it is worthwhile to detect and estimate the amount of silica liberated during the formation and subsequent decomposition of metakaolinite. Various researchers have taken recourse to SiO2 estimation by either of the two techniques.


Spinel Phase Alkali Solution Free Silica Silica Dissolution Exothermic Peak Temperature 
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Copyright information

© Springer India 2014

Authors and Affiliations

  1. 1. Refractory Central Glass & Ceramic Research InstituteJadavpurIndia

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