Silica (Silicon dioxide) is a kind of acidic oxides, normal temperature is solid, chemical formula for the SiO ₂.
Silicon dioxide is insoluble in water, insoluble in acids, but soluble in hydrofluoric acid and hot concentrated phosphoric acid.
Silica(dry basis) % | ≥ 96 |
Heating loss (105°C) % | 4.0-8.0 |
Loss on ignition (1000±25°C)% | ≤7.0 |
PH-value (10%aqueous solution) | 5.0-8.0 |
DBP Oil Absorption Value cm3/g | 2.0-3.5 |
45um sieve Residue % | ≤ 0.5 |
Soluble salt (Na2SO4)% | ≤ 1.5 |
Cu ,mg/kg | ≤ 30 |
Mn ,mg/kg | ≤ 50 |
Fe , mg/kg | ≤300 |
Average grain diameter d50 µm | 4-10 |