Mechanical activation of zircon (ZrSiO4) using planetary milling is carried out.
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The nature of alkali dissolution of mechanically activated zircon is elucidated.
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Kinetics of alkali dissolution of zircon is modelled and explained.
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Activation energy for ZrO2 shows anomalous dependence on milling time.
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Plausible explanation for anomalous dependence of activation energy is presented.