RECOVERY OF GALLIUM FROM COAL FLY-ASH

A study has been made on the extraction of gallium from coal fly ash. A process which includes acid leaching, impurity removal, foam extract ion of gallium and its purification has been suggested. The relatively moderate conditions of temperature, acid strength and time should be chosen in acid leaching to obtain the most efficient extraction of gal lium. The experiments showed that the major elements in fly ash, such as aluminum, iron, silicon and calcium, can be recovered efficiently v ia the proposed flowsheet and that secondary environmental pollution c an be avoided.