• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>International journal of environmental analytical chemistry >Optimisation of solid-state urea clathrate formation as a chemical separation method coupled to compound-specific stable carbon isotope analysis
【24h】

Optimisation of solid-state urea clathrate formation as a chemical separation method coupled to compound-specific stable carbon isotope analysis

机译：固态尿素包合物形成的优化作为化学分离方法，结合化合物特定的稳定碳同位素分析

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Solid-state urea clathrate formation (SSUCF) as a chemical separation method prior to stable carbon isotope fingerprinting of diesel fuel contaminations was studied. The stable carbon isotope ratios (C-13) of n-alkanes in diesel fuel can be used to trace the origin of a contamination. The accurate measurement of the stable isotopic composition of individual compounds requires baseline separation from any other co-eluting compounds. For this purpose silica gel column chromatography (SGCC) and SSUCF were applied. Detailed optimisation of SSUCF was performed: different activators, clathrate formation temperatures, activator volumes, clathrate formation times and sample capacity were investigated. The main benefits of the developed method are reduced clathrate formation time and increased recoveries for lower molecular weight n-alkanes. The recoveries of the developed SSUCF method ranged between 63 and 100% for C10-C24 n-alkanes with relative standard deviation no more than 7%. The precision of the gas chromatography-isotope ratio mass spectrometry measurement was acceptable with a standard deviation of the C-13 values ranging between 0.08 and 0.15. The absence of isotopic fractionation was also investigated.The robustness of the method was tested within a model experiment. Nine different water samples including distilled water, tap water, river water, industrial wastewaters and groundwater samples were spiked with the same diesel fuel. The water samples were extracted with n-hexane and after purification with both SGCC and SSUCF n-alkanes were measured. The C-13 values of n-alkanes were found to be similar for all samples. The importance of sample purification prior to compound-specific isotope analysis (CSIA) was also demonstrated within this model experiment by analysing samples from different stages of the sample preparation.Our results show that the proposed method can remarkably improve the precision of compound-specific stable carbon isotope analysis of n-alkanes originating from diesel contamination of the aquatic environment.
机译：研究了固态脲包合物的形成（SSUCF）作为化学分离方法，然后对柴油机污染物进行稳定的碳同位素指纹分析。柴油中正构烷烃的稳定碳同位素比（C-13）可用于追踪污染源。单个化合物稳定同位素组成的准确测量需要与任何其他共洗脱化合物进行基线分离。为此目的，使用了硅胶柱色谱法（SGCC）和SSUCF。进行了SSUCF的详细优化：研究了不同的活化剂，包合物形成温度，活化剂体积，包合物形成时间和样品容量。该开发方法的主要优点是减少了包合物的形成时间，并提高了低分子量正构烷烃的回收率。对于相对于标准偏差不超过7％的C10-C24正构烷烃，已开发的SSUCF方法的回收率在63％至100％之间。气相色谱-同位素比质谱法的测量精度是可以接受的，C-13值的标准偏差范围为0.08至0.15。还研究了不存在同位素分离的情况。在模型实验中测试了该方法的鲁棒性。用相同的柴油加标了9种不同的水样，包括蒸馏水，自来水，河水，工业废水和地下水样品。用正己烷萃取水样品，并在用SGCC和SSUCF纯化后测量正构烷烃。发现所有样品的正构烷烃的C-13值均相似。在该模型实验中，通过分析样品制备不同阶段的样品，也证明了化合物特异性同位素分析（CSIA）之前样品纯化的重要性。我们的结果表明，该方法可以显着提高化合物特异性稳定剂的精密度来自水生环境柴油污染的正构烷烃的碳同位素分析。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号