摘要
建立高温热水解分解粘土样品,离子色谱快速同时测定其中的氟、氯、溴和碘含量的方法。优化了影响粘土高温热水解的主要参数,得到以下最佳测定条件:2.0 g粘土,反应温度1000℃,停留时间10 min,样品与催化剂V2O5质量比为1∶1,空气流量90 mL/min,15 mL 5.4 mmol/L Na2CO3和5.1 mmol/L NaHCO3混合溶液为粘土释放卤素的吸收液;考察了粘土高温热水解后卤素的赋存形态。结果表明,这些卤素在吸收液中以F!、Cl!、Br!和I!形式存在,且能被离子色谱很好地分离。粘土样品较好的卤素加标回收率和较小的相对标准偏差及土壤标准物质中卤素的评估说明本方法的准确度和精密度良好。分析了4个粘土样品,氟、氯、溴和碘的检出限分别为0.030,0.043,0.09和0.13#g/g,本方法简单、可靠、低消耗和快速,每小时可分析5个样品,可同时分析粘土和其它无机基质中的氟、氯、溴和碘的含量。
A method for the rapid simultaneous determination of halogens （F, C1, Br and I） in clay using pyrohydrolysis for sample digestion and ion chromatography （IC） for the further determination was proposed. The main parameters that influenced on pyrohydrolysis were investigated. After evaluation, the following conditions of pyrohydrolysis were established： 2.0 g clay sample; reactor temperature of 1000 ℃ during 10 min; the mass ratio of clay sample to accelerator V205 1 ： 1 and air flow rate 90 mL/min; 15 mL receiver solution of 5.4 mmol/L Na2CO3 and 5.1 mmol/L NaHCO3. The investigation of analyte in this method using the proposed pyrohydrolysis proeedure indicated that F, C1, Br and I in clay were presented as F-, CI-, Br- and I- in receiver solution which could be well separated by IC. The accuracies of this approach were confirmed by the analysis of four clays spiked with Chinese soil reference materials （ SRMs ） with better recoveries. The limits of deteetion （LOD） were 0. 030, 0. 043, 0. 090, and 0.13 ixg/g for F, C1, Br, and I, respeetively. By using a relatively simple and low cost pyrohydrolysis system, up to five samples can he processed per hour. The developed sample preparation procedure can be routinely employed for F, C1, Br and I determination in clay and other inorganic sample matrixes.
出处
《分析化学》
SCIE
EI
CAS
CSCD
北大核心
2013年第10期1499-1504,共6页
Chinese Journal of Analytical Chemistry
基金
国家自然科学基金(No.40973080)资助
关键词
粘土
卤素
高温热水解
离子色谱
Clay
Halogen
Pyrohydrolysis
Ion chromatography
