It is known that zircon is decomposed at high temperatures in
a reducing media.16 The decomposition temperature is lowered
if a fluxing agent such as NaOH, Na2CO3 or CaCO3 is used. In
this study, to decompose zircon sand, NaOH was chosen as a
fluxing agent due to the fact that the decomposition reaction is
occurred at a lower temperature than in the case of Na2CO3 or
CaCO3 addition