为了建立SuperLig ®620分离水中90 Sr的方法，研究了接触时间、硝酸酸度、柠檬酸铵浓度、干扰核素等对90 Sr在SuperLig ®620固相萃取颗粒上分配系数 Kd 的影响。在0.1 mol／L HNO3介质中，接触时间大于30 min时，Kd 大于1000 mL／g。在 c（H＋）＞1 mmol／L 时，SuperLig®620不吸附137Cs、239 Pu、90 Y ，但可吸附133 Ba。通过调节解吸时柠檬酸铵的浓度，可排除133 Ba对90 Sr分离的干扰。研究了SuperLig®620色层柱分离水中90Sr的方法，将样品调节至0.1 mol／L HNO3上柱，首先用10Vc（柱体积Vc＝0.1 mL）0.1 mol／L HNO3洗涤杂质，然后依次用9Vc 0.1 mol／L柠檬酸铵、13Vc 1.8 mol／L柠檬酸铵解吸90 Sr、133 Ba。该流程对90 Sr的回收率大于99％，对主要干扰核素的去污因子大于3×103，适用于环境水中90 S r的分析。%For setting a procedure of separating 90 Sr in aqueous using SuperLig ® 620 , the performance of SuperLig ® 620 solid phase extraction beads for the adsorption of strontium in aqueous solution was studied .The influences of contact time ,nitric acid concentration ,strontium carrier and ammonium citrate concentration on distribution coefficient Kd were studied .The Kd is more than 1 000 mL/g when contact time is longer than 30 min in 0.1 mol/L HNO3 .The resin can not adsorb any other radionuclides except 133 Ba w hen c(H+ )> 1 mmol/L .90 Sr and 133 Ba can be eluted respectively using different concentrations of ammonium citrate .Based on the results ,a separation proce‐dure of 90 Sr in environmental water samples using SuperLig ® 620 solid phase extraction beads was presented .The optimal separation was found using a 0.1 mol/L HNO3 load solution with a 10Vc 0.1 mol/L HNO3 to wash potential interferences .Then 90Sr was eluted using 9Vc 0.1 mol/L ammonium citrate . The yield of strontium is more than 99% ,and the decontamination factor is more than 3 × 103 .
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