Pyrogenic silica, process for the production thereof and use

US5976480A · kind A · utility

Assignee

• Degussa-Huels AG · DE

Inventors

• Helmut Mangold · Rodenbach, DE
• Dieter Kerner · Midland Park, US
• Peter Kleinschmit · Hanau, DE

Key dates

• Filing date: Jul 30, 1996
• Grant date: Nov 2, 1999
• Expiry date: Jul 30, 2016

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C01P2006/90
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

Pyrogenically produced silica having a specific surface of less than 90 m.sup.2 /g, preferably of less than 60 m.sup.2 /g, and a DBP absorption of less than 60 wt. % (less or equal to 57.30 ml dibutyl phthalate/100 g) is produced by vaporizing silicon halides and/or organosilicon halides, mixing the vapors with a carrier gas, heating the mixture to temperatures definitely above the boiling point of the silicon-halogen compound, mixing with hydrogen and combustion in a known manner in a burner.