Title:
PRODUCTION OF HIGH PURITY METALLIC CHROMIUM
Document Type and Number:
Japanese Patent JP3934686
Kind Code:
B2
Abstract:
PURPOSE: To produce high purity metallic chromium from chromium oxide by treating a mixture under a hydrogen-containing atmosphere, at specific temp. under reduced pressure.
CONSTITUTION: A mixture of powder of chromium oxide, such as Cr2O3 and Cr(OH)3, and carbon compound, such as graphite and chromium carbide, is formed. This mixture is treated under an atmosphere containing gaseous hydrogen, at ≥1300°C under reduced pressure, or, proceed under an atmosphere free from gaseous hydrogen at 1200-1600°C under 0.13 to 26.67KPa(1-200mmHg) pressure in the initial stage of reaction, and, gaseous hydrogen is introduced into the course of the reaction and treatment is done at ≥1300°C under reduced pressure. By this method, high purity metallic chromium can be obtained by a single reducing operation.
Inventors:
Hiromi Miyazaki
Tsuneo Murakami
Kumai Sadakatsu
Yoshio Tanaka
Tsuneo Murakami
Kumai Sadakatsu
Yoshio Tanaka
Application Number:
JP973594A
Publication Date:
June 20, 2007
Filing Date:
January 31, 1994
Export Citation:
Assignee:
Tosoh Corporation
International Classes:
C22B34/32; (IPC1-7): C22B34/32
Domestic Patent References:
| JP63199832A | ||||
| JP63199833A |
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