| 摘要 |
<p>PURPOSE:To separate and recover rare earths and cobalt at a low cost and high yield by dissolving rare earth-cobalt alloy scrap into a hydrochloric acid, adequately adjusting the concn. of chlorine, and bringing the same into contact with an org. solvent contg. a hydrochloric acid addition type ternary amine. CONSTITUTION:The rare earth-cobalt alloy scrap is dissolved into the hydrochloric acid to prepare the aq. soln. contg. rare earth chloride and cobalt chloride. The chlorine concn. in said aq. soln. is so adjusted that the total concn. of the chlorine of the rare earth chloride component and the chlorine of the free hydrochloric acid component in said soln. attains >=4mol/l. The aq. soln. after the adjustment is brought into contact with the org. solvent contg. the hydrochloric acid addition type ternary amine to extract the cobalt chloride in the solvent. The solvent is brought into contact with water to back extract the cobalt chloride in the water. The water is electrolyzed to recover the cobalt. The solvent is recycled to an extraction stage. On the other hand, an oxalic acid is added to the soln. contg. the rare earth chloride after the extraction to allow the entire amt. of the rare earths to settle as the oxalate. The precipitate is filtered, cleaned and dried, and is then thermally decomposed at about 1,000 deg.C, by which the rear earth are recovered in the form of oxide.</p> |
