Abstract: In order to further improve the extraction effect of valuable components in serpentine， taking the iron-bearing serpentine tailings of a concentrator in Qinghai as the research object，the effect of microwave-assisted action on the leaching of magnesium and iron under the condition of fluorite powder as leaching aid is investigated. The results show that when fluorite powder is used as leaching aid，the leaching rate of Mg and TFe is the best under the leaching conditions of microwave time 3 min，micro⁃ wave power 400 W，leaching temperature 70 ℃，leaching time 30 min，sulfuric acid concentration 4.0 mol/L and fluorite powder dosage 3%，reaching 97.02% and 50.90%，respectively.On this basis，the mag⁃ nesium ion in the leaching solution is recovered by precipitation method. The pH value of the leaching so⁃ lution is adjusted to 8.5. After heating and stirring at 40 ℃ for 25 min，0.05 g/L non-ionic polyacrylamide is added. After slight stirring，it is allowed to stand for 10 min and filter. The impurities such as iron ions in the crude solution of magnesium sulfate can be removed，and the removal rate is 99.84%.After that， the pH value of the filtrate is adjusted to 11.0 under continuous stirring conditions，and the crude product of Mg（OH）2 is obtained after static aging for 60 min. The purity of Mg（OH）2 reaches 95.73%，which pro⁃ vides a new technical path for the resource utilization of serpentine tailings.

Key words: iron-containing serpentine tailings, leaching, fluorite leaching aid agent, microwave as? sistance, magnesium hydroxide