High yield manufacturing process for silicon carbide

US5190737A · kind A · utility

Assignee

• THE DOW CHEMICAL COMPANY · US

Inventors

• Alan W. Weimer · Niwot, US
• Raymond P. Roach · Midland, US
• John P. Henley · Midland, US

Key dates

• Filing date: Apr 30, 1991
• Grant date: Mar 2, 1993
• Expiry date: Apr 30, 2011

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C01P2006/80
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A process for preparing silicon carbide by carbothermal reduction which includes transporting, in a gaseous medium, a particulate reactive mixture of a silica source and a carbon source through a reaction zone. The heating rate of the atmosphere within the reaction zone is such that substantially all of the reactive mixture is heated at a heating rate of at least about 100.degree. C./second until an elevated temperature of at least 1800.degree. C. is reached. Either (1) carbon monoxide is added to the reaction zone or (2) a carbon monoxide level in the reaction is achieved in order to provide at least about 30 mole percent of the gases exiting the reaction zone to achieve a higher yield of silicon carbide.