Mark Noah, Arthur Jennifer, Dontsova Katerina, Brusseau Mark, Taylor Susan, Šimůnek Jiří
Dept. of Soil, Water, and Environmental Science, Univ. of Arizona, 1177 E. Fourth St., PO Box 210038, Shantz Bldg. #38, Tucson, AZ 85721-0038, USA.
Dept. of Soil, Water, and Environmental Science, Univ. of Arizona, 1177 E. Fourth St., PO Box 210038, Shantz Bldg. #38, Tucson, AZ 85721-0038, USA; Biosphere 2, University of Arizona, Marshall Building, Room 523, 845 N. Park Avenue, Tucson, AZ 85721-0158, USA.
Chemosphere. 2017 Mar;171:427-434. doi: 10.1016/j.chemosphere.2016.12.067. Epub 2016 Dec 18.
Development of the new, insensitive, energetic compound, NTO (3-nitro-1,2,4-triazol-5-one), creates need for the data on NTO's fate and transport to predict its behavior in the environment and potential for groundwater contamination. To measure the transport of NTO in soils, we conducted miscible-displacement experiments under steady state and interrupted flow conditions using eight soils having varying physical and geochemical properties. The breakthrough curve (BTC) data were analyzed using temporal moment analysis and simulated using HYDRUS-1D to determine transport parameters and better understand the mechanisms of sorption and transformation. Parameters determined from the miscible-displacement study were compared to results obtained from batch experiments conducted for the same soils, and examined in relation to soil properties. Column NTO linear adsorption coefficients (K) were low and correlated well (P = 0.000049) with measurements from the batch studies. NTO transformation rate constants increased and NTO recovery decreased with increase in soil organic carbon (OC) content. Autoclaved soils had slower transformation rates and greater NTO recoveries indicating that microorganisms play a role in NTO transformation. In addition, the transformation rate increased with time in soils with higher OC. Monod-type kinetics was implemented in HYDRUS-1D to simulate the observed increase in transformation rate with time. We think this phenomenon is due to bacterial growth. Results indicate very low adsorption of NTO in a range of soils, but natural attenuation through transformation that, depending on soil OC content and hydraulic residence time, could result in complete removal of NTO.
新型不敏感高能化合物3-硝基-1,2,4-三唑-5-酮（NTO）的研发，使得需要获取有关NTO归宿和迁移的数据，以预测其在环境中的行为以及对地下水污染的可能性。为了测量NTO在土壤中的迁移，我们使用了8种具有不同物理和地球化学性质的土壤，在稳态和间歇流条件下进行了混溶置换实验。利用时间矩分析对穿透曲线（BTC）数据进行了分析，并使用HYDRUS-1D进行了模拟，以确定迁移参数，并更好地理解吸附和转化机制。将混溶置换研究确定的参数与相同土壤的批次实验结果进行了比较，并结合土壤性质进行了考察。柱NTO线性吸附系数（K）较低，与批次研究的测量结果相关性良好（P = 0.000049）。随着土壤有机碳（OC）含量的增加，NTO转化速率常数增加，NTO回收率降低。经过高压灭菌的土壤转化速率较慢，NTO回收率较高，这表明微生物在NTO转化中发挥了作用。此外，在OC含量较高的土壤中，转化速率随时间增加。在HYDRUS-1D中采用莫诺德型动力学来模拟观察到的转化速率随时间的增加。我们认为这种现象是由于细菌生长所致。结果表明，NTO在一系列土壤中的吸附非常低，但通过转化实现的自然衰减，根据土壤OC含量和水力停留时间，可能导致NTO被完全去除。
