Kemper Jerome M, Ammar Emaan, Mitch William A
Department of Chemical Engineering, Yale University, Mason Lab 313b, 9 Hillhouse Avenue New Haven, Connecticut 06520, USA.
Environ Sci Technol. 2008 Mar 15;42(6):2118-23. doi: 10.1021/es702402a.
We report that hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) was rapidly destroyed by sulfides in the presence of black carbon, forming nitrite and formaldehyde, rather than toxic nitrosated reduction products. Although traditionally viewed as inactive sorbents, black carbons have been noted to participate in the destruction of certain contaminants, such as azo dyes, via quinonoid groups. However, in our experiments sulfide modification of quinones did not seem to be involved. Although at least 1.2 mM sulfides were needed for the reaction to proceed, abiotic natural attenuation of RDX in marine sediments may occur, because these concentrations are found in certain marine sediments, together with black carbon. In the absence of natural black carbons, synthetic black carbons, such as activated carbon, may be added to sediments. As compared with other in situ techniques, such as bioremediation and zero-valent iron cutoff trenches, which often generate nitrosated byproducts, this in situ, abiotic technique may be an attractive alternative.
我们报告称，在黑碳存在的情况下，六氢-1,3,5-三硝基-1,3,5-三嗪（RDX）会被硫化物迅速分解，生成亚硝酸盐和甲醛，而非有毒的亚硝化还原产物。尽管传统上认为黑碳是无活性的吸附剂，但人们已注意到黑碳会通过醌类基团参与某些污染物（如偶氮染料）的分解。然而，在我们的实验中，醌类的硫化物改性似乎并未参与其中。尽管反应进行至少需要1.2 mM的硫化物，但RDX在海洋沉积物中可能会发生非生物自然衰减，因为在某些海洋沉积物中发现了这些浓度的硫化物以及黑碳。在没有天然黑碳的情况下，可以向沉积物中添加合成黑碳，如活性炭。与其他原位技术（如生物修复和零价铁截留沟，这些技术常常会产生亚硝化副产物）相比，这种原位非生物技术可能是一个有吸引力的替代方案。
