| In this paper,the current situation and progress on the methods of separation and enrichment of rare earth elements at home and abroad were reviewed.Based on the characteristic of absorption of some metal ion for separation from other ions under certain conditions by special functional groups in the molecule of exchange fiber,the separation and enrichment of trace rare earth elements La,Nd,Eu,Gd,Er and Yb from various matrix were investigated using polypropylene based strong acidic cation ion exchange fiber, polypropylene based weak acidic cation exchange fiber,and polyacrylonitrile based amphoteric ion exchange fiber respectively with ICP-AES.1 A method of enrich trace rare earth elements by polypropylene based strong acid cation ion exchange fiber was studied.The conditions of enrichment and eluent were optimized.When the pH of pregnant solution was 3,rare earth elements was enriched quantitatively at the flow rate within 14 mL·min-1.Then it was desorbed from the column completely by 10 mL 2.5 mol·L-1HNO3.The adsorption capacity were La 130 mg·g-1,Nd 142 mg·g-1,Eu 122 mg·g-1,Gd 151 mg·g-1,Er 104 mg·g-1,Yb 134 mg·g-1.The coexisting elements of K,Na,Mg,Ca, Ba,Cu,Zn,Fe and Al could be removed by pre-eluting with 0.5 mol·L-1HNO3. The detection limit of the method was La 0.016 ng·mL-1,Nd 0.051 ng·mL-1,Eu 0.006 ng·mL-1,Gd 0.029 ng·mL-1,Er 0.048 ng·mL-1,Yb 0.006 ng·mL-1,the recovery was in the range of 94.5%～103%,and the RSD was between 0.7%～5.2 %.The method was validated by the determination of trace rare earth elements in water,artificial samples,orange leaf,and GSD-11 samples.2 A method of enrich trace rare earth elements by polypropylene based weak acid cation ion exchange fiber was studied.The conditions of enrichment and eluent were optimized.When the pH of pregnant solution was 5,rare earth elements was enriched quantitatively at the flow rate within 10 mL·min-1.Then it was desorbed from the column completely by 10 mL 1.0 mol·L-1HCl.The adsorption capacity were La 86.5 mg·g-1,Nd 98.2 mg·g-1,Eu 98.7 mg·g-1,Gd 99.2 mg·g-1,Er 84.9 mg·g-1,Yb 91.5 mg·g-1.The detection limit of the method was La 0.015 ng·mL-1,Nd 0.039 ng·mL-1,Eu 0.0090 ng·mL-1,Gd 0.030 ng·mL-1, Er 0.015 ng·mL-1,Yb 0.0090 ng·mL-1,the recovery was in the range of 91.8%-103%,and the RSD was between 0.3%～5.6%.The method was validated by the determination of trace rare earth elements in water and artificial samples.3 A method of enrich trace rare earth elements by polyacrylonitrile based amphoteric ion exchange fiber was studied.The conditions of enrichment and eluent were optimized.When the pH of pregnant solution was 5,rare earth elements was enriched quantitatively at the flow rate within 8 mL·min-1.Then it was desorbed from the column completely by 10 mL 1.5 mol·L-1HNO3.The adsorption capacity were La 7.32 mg·g-1,Nd 7.61 mg·g-1,Eu 8.04 mg·g-1,Gd 7.95 mg·g-1,Er 9.12 mg·g-1,Yb 8.49 mg·g-1.The detection limit of the method was La 0.032 ng·mL-1,Nd 0.068 ng·mL-1,Eu 0.033 ng·mL-1,Gd 0.053 ng·mL-1, Er 0.045 ng·mL-1,Yb 0.019 ng·mL-1,the recovery was in the range of 90.0%～101%,and the RSD was between 0.4%～5.3%.The method was validated by the determination of trace rare earth elements in water and artificial samples.
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