METHOD FOR EXTRACTING GALLIUM FROM FLY ASH

摘要

Disclosed is a method for extracting gallium from fly ash, which comprises the following steps: crushing the fly ash and removing Fe by magnetic separation, then dissolving it by using hydrochloric acid (2) to obtain hydrochloric acid leachate; adsorbing gallium in the hydrochloric acid leachate with macroporous cation resin, followed by eluting to obtain the eluent (5) containing gallium; adding sodium hydroxide (6) solution into the eluent containing gallium to react and obtaining sodium meta-aluminate solution containing gallium (8); introducing CO2 into the sodium meta-aluminate solution containing gallium (8) for carbonation, followed by separating gallium from aluminium and obtaining aluminium-gallium double salt (15) with the gallium to alumina mass ratio being more than 1:340; adding the aluminium-gallium double salt (15) into sodium hydroxide (17) solution to react, followed by concentration to obtain alkali solution containing gallium and aluminium; electrolyzing (10) the alkali solution containing gallium and aluminium to obtain metal gallium (11). The method simplifies the process and improves extraction yield of gallium.