Abstract:

The purification of the high loss, low-grade diatomite production in Inner Mongolia was carried out by water separation-calcination process. The effects of the times of water separation and calcination conditions on the purification of diatomite were investigated and the characteristics of purified diatomite were conducted by XRD, FTIR, SEM, BET and chemical analysis in this study. The results indicated that the water separation can efficiently remove the quartz, feldspar and clayey impurities in diatomite and the organic matter can be removed by calcination at 600 ℃. Consequently, the silica content fraction in purified diatomite was above 82.98%, the specific surface area was 44.5 m2/g and the tap density was 21 mL/10g. In the absence of air condition, the purified carbonized-diatomite had a good compatibility with rubber which can be widely used instead of semi-reinforcing carbon black.

Key words: diatomite, purification, water-heating, carbonation