煤炭中铅同位素分析方法研究  

Analytical Method of Pb Isotopes in Coal

作　　者：刘缓缓 张丽华[1] 崔大庆 朱留超[1] 刘焕良[1] 沈彦[1] 赵立飞[1] 谈树苹[1] 

机构地区：[1]中国原子能科学研究院放射化学研究所,北京102413

出　　处：《同位素》2017年第4期232-242,共11页Journal of Isotopes

摘　　要：同位素比值是污染源解析的基础,为了探索燃煤污染源解析的可行性,本研究建立煤炭中铅同位素的分析方法。采用灰化-微波消解相结合的方式,将煤样转换为溶液状态,用PB树脂(冠醚类)萃取色层法,将铅和大量基体元素有效分离,用多接收电感耦合等离子体质谱法测定铅同位素比值。利用NIST 981标定天然铅溶液的铅同位素比值,应用建立的分析方法,测定^(208)Pb/^(207)Pb、^(206)Pb/^(207)Pb的同位素比值,相对误差小于0.03%。钠、镁、铝、铁、钛、锰等元素的去污系数均大于400。结果表明,该方法有效、可靠,测定标准煤样(NIST 1635a、NIST 1632d)、山西大同煤样和攀枝花煤样的^(208)Pb/^(207)Pb、^(206)Pb/^(207)Pb同位素比值,精密度均大于0.2%,两地煤样同位素比值变异为6%~10%,初步验证了建立全国煤炭中铅同位素比值背景数据库的可行性。As the basis method for the pollution source apportionment,the isotope ratios were applied for analysis Pb isotopes in coal to explore the feasibility of coal pollution source apportionment.A method was established to analysis Pb isotopes in coal.First,the coal samples were dissolved by the combination of ashing and microwave digestion.Then by using PB resin extraction chromatography,Pb and a large number of matrix elements were effectively separated.After separation,the Pb isotope ratios were determined by multi-collector inductively coupled plasma mass spectrometry.The Pb isotopic ratios of natural Pb solution were calibrated with NIST 981.Using established analytical method,the measured relative error of ^（208）Pb/^（207）Pb,^（206）Pb/^（207）Pb in natural Pb solution were less than 0.03%,the decontamination coefficients of sodium,magnesium,aluminium,iron,titanium and manganese were more than 400.The results showed that the method was effective and reliable.By measuring the standard coal samples（NIST1635 a,NIST 1632 d）,Shanxi Datong and Panzhihua coal samples,it was found that therelative standard deviation of ^（208）Pb/^（207）Pb,^（206）Pb/^（207）Pb were less than 0.2%.The ratio difference of ^（208）Pb/^（207）b and ^（206）Pb/^（207）Pb between Datong coal and Panzhihua coal was about 6% ~10%.Such a big difference proved that it was feasible to establish a Pb isotope background database about the coal in China.

关 键 词：煤炭 铅同位素比值 PB树脂 多接收电感耦合等离子体质谱 

分 类 号：TL364.5[核科学技术—核技术及应用]