| An optimum process for the production of technical grade zirconia was studied by employing the method of caustic fritting of zircon. The optimum conditions for the production of caustic zircon frit was as follows; 1.4 of caustic to zircon sand weight ratio, 650-700 deg. C. of reaction temperatures and 10-60 minutes of reaction times. The frit was leached by water and the 6∼7% of sodium content remained after leaching was eliminated by digesting it with dilute HCl solution in an autoclave. The digested product was structually amorphous but when roasted at 700 deg. C. for one hour, it became cubic zirconia. The composition of the final product was 1.07% of SiO₂, trace of sodium, 0.37% of Al₂O₃, 0.24% of Fe₂O₃, 0.36% of TiO₂, and 97.96% of ZrO₂. |
|
