Patent ID: 8728296

Claim:
A method for extracting gallium from fly ash, comprising the following steps: a) crushing the fly ash to a size of 100 mesh or smaller, removing iron by wet magnetic separation such that the ferric oxides content in the fly ash is reduced to 1.0 wt % or less, then adding hydrochloric acid into the de-ironed fly ash for an acid-leaching reaction, and subjecting the reaction product to solid-liquid separation, so as to yield a hydrochloric leachate having a pH value in the range of 1-3; b) adsorbing gallium in the hydrochloric leachate by passing the same through a column loaded with a strongly acidic styrene-based cation-exchange resin; eluting the column with water or hydrochloric acid as an eluting agent when the adsorption reaches saturation to obtain a gallium-containing eluent; c) masking ferric ions in the gallium-containing eluent by a masking agent followed by passing the masked eluent through the column loaded with a strongly acidic styrene-based cation-exchange resin; eluting the column with water or hydrochloric acid as an eluting agent when the adsorption reaches saturation to obtain a second eluent; and d) adding an alkali solution into the second eluent, removing precipitates by filtering after reaction, and concentrating the filtrate till both gallium content and sodium hydroxide content are 1 mol/l or more, then electrolyzing the concentrated filtrate to obtain metal gallium, wherein in the acid-leaching reaction of step a), the reaction temperature is 100-200° C., the reaction pressure is 0.1-2.5 MPa.