PROCESS FOR RECYCLING RARE EARTHS IN PERMANENT MAGNET SCRAP OF ELECTRONIC WASTE

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A process for recycling rare earths in permanent magnet scrap of electronic waste comprises : 1) oxidizing and smelting the scrap at a high temperature to obtain alloy particles and levigating the alloy particles; 2) at a high temperature, roasting the alloy particles with a chloride and carbon powder; 3) recycling borates and chlorides with a tail gas absorption liquid through multiple steps of recrystallization; 4) subjecting the powder after chloridizing roasting to two-stage countercurrent washing with hot diluted hydrochloric acid, to dissolve soluble metal chlorides; 5) passing the filtrate through hydrogen sulfide gas under an acid condition so that cobalt and nickel are completely precipitated, and then removing ferric ions by means of precipitation; extracting and separating Pr, Nd, Sm, and Dy, and then precipitating the products with oxalic acid and roasting same to obtain rare earth oxides; 6) subjecting the cobalt and nickel sulfides slag to sulfatizing roasting, after dissolving the product in an acid, extracting and separating cobalt and nickel, and recycling the cobalt and nickel.