Chemical Composition And Classification Of Zircon Brick

Zircon brick contains 67.2% ZrO2 and 32.8% SiO2. Because of similar chemical properties of Zr and Hf,so zircon brick often contains a certain amount of Hf. Under normal circumstances, Hf/Zr is closed to 0.007, but individual case can be as high as 0.6. In addition, zircon brick also contains a small amount of rare radioactive elements, such as TR(Th,Y,Ce), Nb, Ta, U, etc. and mixed material such as CaO, Al2O3, Fe2O3, and generally, Fe2O3≥0.35%，CaO 0.05%~4%. 

 

According to the difference of impurities contained in zircon brick, zircon brick can be divided into the following several variants.

 

Yamaguchi stone: containing high contents of TR2O3 which can up to 9.2%, (Nb, Ta)2O5 which can up to 7.69%, the contents of U and Th is also high, but not contain P2O5.

 

Cyrtolite: Radioactive, TR2O3 and U3O8 containing high, so often the lattice is destroyed and not by vitrification, and also containing rich water.

 

Beryllium zircon: contain high contents of BeO which can reach 14.73%.

 

Water zircon stone: Rich in radioactive elements, while the content of water is up to 2% to 12%.

 

Rich hafnium zircon: HfO2 is up to 24%, TR2O3 reaches 1%~4%, not contain the elements of U and Th.