Ul'yanovskii N V, Kosyakov D S, Pikovskoi I I, Khabarov Yu G
Core Facility Center "Arktika", M.V. Lomonosov Northern (Arctic) Federal University, Northern Dvina Emb. 17, Arkhangelsk, 163002, Russia.
Core Facility Center "Arktika", M.V. Lomonosov Northern (Arctic) Federal University, Northern Dvina Emb. 17, Arkhangelsk, 163002, Russia.
Chemosphere. 2017 May;174:66-75. doi: 10.1016/j.chemosphere.2017.01.118. Epub 2017 Jan 26.
1,1-Dimethylhydrazine is used as a fuel for carrier rockets in the majority of countries implementing space exploration programs. Being highly reactive, 1,1-dimethylhydrazine easily undergoes oxidative transformation with the formation of a number of toxic, mutagenic, and teratogenic compounds. The use of high-resolution mass spectrometry for the study of the reaction of 1,1-dimethylhydrazine oxidation with hydrogen peroxide in aqueous solution allowed us to find hundreds of nitrogen-containing products of the CHN and CHNO classes, formed via radical processes. The vast majority of the compounds have not been previously considered as possible products of the transformation of rocket fuel. We have shown that the oxidation of 1,1-dimethylhydrazine proceeds in two stages, with the formation of a great number of complex unstable intermediates that contain up to ten nitrogen atoms. These intermediates are subsequently converted into final reaction products with a concomitant decrease in the average molecular weight. The intermediates and final products of the oxidative transformation of 1,1-dimethylhydrazine were characterised on the basis of their elemental composition using van Krevelen diagrams and possible compounds corresponding to the most intense peaks in the mass spectra were proposed. The data obtained are indicative of the presence of the following classes of heterocyclic nitrogen-containing compounds among the oxidation products: imines, piperidines, pyrrolidines, dihydropyrazoles, dihydroimidazoles, triazoles, aminotriazines, and tetrazines. The results obtained open up possibilities for the targeted search and identification of new toxic products of the degradation of rocket fuel and, as a result, a more adequate assessment of the ecological consequences of space-rocket activity.
在大多数实施太空探索计划的国家，1,1 - 二甲基肼被用作运载火箭的燃料。1,1 - 二甲基肼具有高反应活性，容易发生氧化转化，形成许多有毒、致突变和致畸的化合物。利用高分辨率质谱研究1,1 - 二甲基肼在水溶液中与过氧化氢的氧化反应，使我们发现了数百种通过自由基过程形成的CHN和CHNO类含氮产物。绝大多数这些化合物以前未被视为火箭燃料转化的可能产物。我们已经表明，1,1 - 二甲基肼的氧化分两个阶段进行，形成大量含有多达十个氮原子的复杂不稳定中间体。这些中间体随后转化为最终反应产物，同时平均分子量降低。基于元素组成，利用范克雷维伦图对1,1 - 二甲基肼氧化转化的中间体和最终产物进行了表征，并提出了与质谱中最强峰相对应的可能化合物。所获得的数据表明氧化产物中存在以下几类含氮杂环化合物：亚胺、哌啶、吡咯烷、二氢吡唑、二氢咪唑、三唑、氨基三嗪和四嗪。所获得的结果为有针对性地搜索和鉴定火箭燃料降解产生的新有毒产物提供了可能性，从而更充分地评估太空火箭活动的生态后果。
