EP 0963345 A1 19991215 - HYDROPHOBIC SILICA GELS WITH REDUCED SURFACE AREA
Title (en)
HYDROPHOBIC SILICA GELS WITH REDUCED SURFACE AREA
Title (de)
HYDROPHOBE KIESLSÄUREGELE MIT REDUZIERTER SPEZIFISCHER OBERFLÄCHE
Title (fr)
GELS DE SILICE HYDROPHOBES PRESENTANT UNE ZONE SUPERFICIELLE LIMITEE
Publication
Application
Priority
- US 9803273 W 19980218
- US 80600597 A 19970224
Abstract (en)
[origin: WO9837020A1] The present invention is hydrophobic silica gels having reduced surface area and a method for their preparation. The method comprises three steps, where in the first step a mixture comprising a silica hydrosol and colloidal silica is formed. In the second step the mixture is heat treated in the presence of a strong mineral acid at a pH less than about 1 to form a silica hydrogel having incorporated therein colloidal silica. In the third step the silica hydrogel is contacted with an organosilicon compound in the presence of a catalytic amount of a strong acid to effect hydrophobing of the silica hydrogel thereby forming a hydrophobic silica gel having a surface area within a range of about 100 m<2>/g to 450 m<2>/g as measured in the dry state. In a preferred method the hydrophobic silica gel is contacted with a sufficient quantity of an organic solvent immiscible with water to convert the hydrophobic silica hydrogel into a hydrophobic silica organogel.
IPC 1-7
IPC 8 full level
C01B 33/159 (2006.01); C01B 33/16 (2006.01); C09C 1/30 (2006.01)
CPC (source: EP KR)
C01B 33/16 (2013.01 - EP KR); C09C 1/3081 (2013.01 - EP); C01P 2004/60 (2013.01 - EP); C01P 2006/12 (2013.01 - EP); C01P 2006/90 (2013.01 - EP)
Citation (search report)
See references of WO 9837020A1
Designated contracting state (EPC)
BE DE ES FR GB IT
DOCDB simple family (publication)
WO 9837020 A1 19980827; AU 6660598 A 19980909; BR 9810408 A 20000822; CA 2280795 A1 19980827; CN 1248226 A 20000322; EP 0963345 A1 19991215; JP 2001513066 A 20010828; KR 20000075594 A 20001226
DOCDB simple family (application)
US 9803273 W 19980218; AU 6660598 A 19980218; BR 9810408 A 19980218; CA 2280795 A 19980218; CN 98802755 A 19980218; EP 98908610 A 19980218; JP 53688398 A 19980218; KR 19997007655 A 19990823