本文選題：Li分離純化 + Li同位素測定�。� 參考：《地球化學(xué)》2017年06期

【摘要】：為了高效地從地質(zhì)/環(huán)境樣品中分離純化Li元素并進行Li同位素測定,經(jīng)反復(fù)實驗和改良發(fā)現(xiàn):采用8 m L容積(樹脂體積)離子交換柱,選取AG 50W-X12陽離子交換樹脂,以0.5 mol/L HNO3為淋洗液,過柱一次,并收集20~48 m L區(qū)間的淋洗液,即可一步實現(xiàn)Li的完全純化分離。對于高鹽樣品,建議過柱兩次確保Na/Li1,以達到上機測試的要求。由多種單元素標(biāo)準混合的工作溶液(IEECAS-Li)經(jīng)此流程分離后,采用Neptune Plus MC-ICP-MS測量得到的δ7Li值為8.31‰±0.12‰,與未混合的標(biāo)準值(8.33‰±0.20‰)在誤差范圍內(nèi)一致。采用此流程,獲得的巖石標(biāo)準物質(zhì)AGV-2、BHVO-2和海水標(biāo)準物質(zhì)NASS-6的δ7Li值(2 s.d.,n=5)也與推薦值一致,分別為6.83‰±0.75‰、4.32‰±0.33‰和31.10‰±0.60‰。由此,我們建立了一套高效分離純化Li及其同位素的MC-ICP-MS測試程序。將該程序用到Li含量在15 ng/g~90μg/g之間的實際樣品中,δ7Li的長期內(nèi)精度均好于0.30‰,且重現(xiàn)性高,表明該方法的分析精度和準確度都達到了國際標(biāo)準水平。尤為重要的是,本方法可用于精確測量含痕量Li的環(huán)境樣品的Li同位素組成。
[Abstract]:In order to separate and purify Li elements from geological / environmental samples and determine Li isotopes efficiently, repeated experiments and improvements showed that AG 50W-X12 cation exchange resins were selected with 8 mL volume (resin volume) ion exchange column. Using 0. 5 mol/L HNO3 as eluant, once through column, and collecting the eluent in the range of 20 ~ 48 mL, the complete purification and separation of Li can be realized in one step. For high salt samples, it is recommended that the Na / L 1 should be guaranteed twice to meet the test requirements. The 未 7Li measured by Neptune Plus MC-ICP-MS is 8.31 鈥，

本文編號：1826190