Title:
MANUFACTURE OF HYDROGEN FLUORIDE
Document Type and Number:
Japanese Patent JPS57135701
Kind Code:
A
Abstract:
In the production of hydrogen fluoride gas for the production of AlF3 by the reaction of fluorspar with concentrated sulphuric acid a small amount of aluminium sulphate is introduced into the reactive mix to assist in the retention of phosphorous compounds in the solid residues of the reaction and thus reduce the phosphorous content of the gaseous HF. Aluminium sulphate may be added as alum or may be generated in situ in the sulphuric acid by addition of an alumina hydrate, preferably before the acid is brought into contact with fluorspar. The addition of a small amount of calcium carbonate to the fluorspar also improves retention of phosphorous compounds in the solid residues in some instances.
Inventors:
BOODAN GUNIRA
Application Number:
JP21610681A
Publication Date:
August 21, 1982
Filing Date:
December 29, 1981
Export Citation:
Assignee:
ALCAN INT LTD
International Classes:
C01B7/19; (IPC1-7): C01B7/19
Foreign References:
| US4078047A | 1978-03-07 |