| 摘要 |
PURPOSE:To efficiently recover rare earth elements by passing an aq. soln. consisting of rare earth elements and a complex forming agent through a strong acidic cation exchange resin layer and thereafter passing an acid aq. soln. through the column to obtain the rare earth elements aq. soln. CONSTITUTION:A mixed aq. soln. consisting of rare earth elements and an aminoacetic acid-base complex forming agent is passed through a column packed with proton type strong acidic cation exchange resin and rare earth elements are selectively adsorbed and the complex forming agent aq. soln. free from rare earth elements is obtained. Then an acid aq. soln. having 3-8N concn. is passed through this column at amount (but incorporating acid not less than equivalent of adsorbed rare earth elements) of not more than 1/10 of the above- mentioned aq. soln. as volume ratio and rare earth elements are recovered. A precipitate recovering agent of 1.0-2.0 equivalent times is added to the obtained rare earth elements aq. soln. and thereby rare earth elements are precipitated, separated and recovered. |
