Patent ID: 6093376
Filing Date: 2000-07-25
Classification: C01F,C22B,Y02P

Abstract:
An ion exchange process for selectively eluting rare earth elements comprising, the steps of:preparing an ion exchange separation column containing an iminodiacetic resin;conditioning said iminodiacetic resin by contacting a first portion of the iminodiacetic resin with an acid to place the first portion in a hydrogen form;contacting a second portion of the iminodiacetic resin with an intermediate buffer to place the second portion in an ammonium form;saturating both said first and second portions of the iminodiacetic resin with a solution of rare-earth ions;absorbing the rare earth ions in the separation column;arranging the sequence of the first and second portions in the separation column so that the first portion is downstream of the second portion; andeluting the rare earth ions from the separation column with a chelating agent.