Stable isotopes have been widely used to monitor remediation of environmental contaminants over the last decades. This approach gives a good mechanistic description of natural or assisted degradation of organic pollutants, such as methyl tert-butyl ether (MTBE). Since abiotic degradation seems to be the most promising assisted attenuation method, the isotopic fractionation associated with oxidation and hydrolysis processes need to be further investigated in order to understand better these processes and make their monitoring more efficient. In this study, position-specific isotope effects (PSIEs) associated with permanganate oxidation and acid hydrolysis of MTBE were determined using isotope ratio monitoring by 13C Nuclear Magnetic Resonance Spectrometry (irm-13C NMR) combined with isotope ratio monitoring by Mass Spectrometry (irm-MS). The use of this Position-Specific Isotopic Analysis (PSIA) method makes it possible to observe a specific normal isotope effect (IE) associated with each of these two abiotic degradation mechanisms. The present work demonstrates that the 13C isotope pattern of the main degradation product, tert-butyl alcohol (TBA), depends on the chemical reaction by which it is produced. Furthermore, this study also demonstrates that PSIA at natural abundance can give new insights into reaction mechanisms and that this methodology is very promising for the future of modeling the remediation of organic contaminants.

中文翻译：

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甲基叔丁基醚的高锰酸盐氧化和酸水解过程中的分子内同位素效应。

在过去的几十年中，稳定同位素已广泛用于监测环境污染物的修复。这种方法很好地描述了有机污染物（例如甲基叔丁基醚（MTBE））的自然降解或辅助降解。由于非生物降解似乎是最有前途的辅助衰减方法，因此需要进一步研究与氧化和水解过程相关的同位素分馏，以便更好地了解这些过程并提高其监测效率。在这项研究中，使用13C核磁共振波谱（irm-13C NMR）监测同位素比率和质谱法（irm-多发性硬化症）。使用这种特定位置同位素分析（PSIA）方法可以观察到与这两种非生物降解机制中的每一个相关的特定正常同位素效应（IE）。本工作表明，主要降解产物叔丁醇（TBA）的13 C同位素模式取决于其产生的化学反应。此外，这项研究还表明，自然丰度的PSIA可以为反应机理提供新的见识，并且这种方法学对于将来对有机污染物的修复进行建模非常有希望。目前的工作表明，主要降解产物叔丁醇（TBA）的13 C同位素模式取决于其产生的化学反应。此外，这项研究还表明，自然丰度的PSIA可以为反应机理提供新的见识，并且这种方法学对于有机污染物修复的未来建模非常有前途。目前的工作表明，主要降解产物叔丁醇（TBA）的13 C同位素模式取决于其产生的化学反应。此外，这项研究还表明，自然丰度的PSIA可以为反应机理提供新的见识，并且这种方法学对于将来对有机污染物的修复进行建模非常有希望。