| abstract |
A method of recovering fumed hydrophobic SiO2, produced by the flame hydrolysis of a ternary azeotrope of H2SiF6, HF, and H2O, is disclosed. The method involves passing the fumed hydrophobic silica, as it leaves the combustion chamber, through a nonclassifying agglomerator at a residence (travel) time of from about 0.5 to several seconds, preferably about 1.0 to about 5.0 seconds, then separating the fumed silica from the product stream in a cyclone separator or other means for collecting dispersoids. |