METHOD OF PREPARING HYDROPHOBIC SILICA

摘要

The present invention provides a method of treating silica, wherein dry silica is contacted with a reaction medium consisting essentially of concentrated aqueous acid and a hydrophobing agent selected from the group consisting of organosiloxanes and organochlorosilanes. The silica is then reacted with the hydrophobing agent in the reaction medium for about 90 minutes or less at a temperature from about 10 DEG C to about 40 DEG C to provide a hydrophobic treated silica. The hydrophobic treated silica then is recovered.