Page 93 - Encyclopedia of Chemical Compounds 3 Vols

ALUMINUM FLUORIDE

Aluminum fluoride. Red atom
is aluminum and green atoms
are fluorine. PUBLISH E R S
RESOURCE GROUP

between dry alumina trihydrate and gaseous hydrogen fluor-
ide. The third method involves the addition of fluorosilicic
acid (H 2 SiF 6 ) to alumina trihdrate. The last of these methods
is commercially attractive because fluorosilicic acid is
obtained inexpensively as a by-product in the production of
fertilizers and phosphoric acid.

COMMON USES AND POTENTIAL HAZARDS
The primary use of aluminum fluoride is in the produc-
tion of aluminum metal. In that process, aluminum is
extracted from one of its compounds (usually aluminum
oxide) by passing an electric current through the molten
(melted) compound. The addition of aluminum fluoride to
the raw materials used in the process reduces the temperature
at which the reaction occurs and improves the conductivity of
the molten compound.
Some other uses of aluminum fluoride include:
• As a catalyst in the synthesis of organic compounds;

• To suppress the process of fermentation in the wine-
and beer-making industries;

42 CHEMICAL COMPOUNDS