The production of nanoparticles (NPs) has increased significantly, given that they have numerous commercial and medical applications. There might have some risk associated with the release of these NPs in the environment. To assess the possible risk of releases of NPs in the groundwater, it is important to evaluate the fate and transport behaviour of NPs through porous media. The objective of this study is, therefore, to evaluate the transport behaviour of widely used NPs [i.e., silver (Ag), iron oxide (Fe_xO_y), titanium dioxide (TiO₂) and zinc oxide (ZnO)] through porous media in the presence and/or absence of organic matter [i.e., humic acid (HA)] under controlled de-ionized and natural groundwater condition. To achieve the objective, first, the detailed characterizations of NPs are carried out in the presence and absence of HA. Column transport experiments were performed using a 1-D sand-packed column. Different NPs were injected from one end of the column with a flow rate of 0.0054 cm/sec. The result suggests that nAg, nTiO_2, and nZnO particles are colloidal stable in the suspension, while nFe_xO_y particles tend to aggregate and settle down very rapidly. However, in the presence of HA, the colloidal stability of nFe_xO_y in the suspension increases significantly. Evaluation of transport behaviour of different metal NPs suggests that a high amount of nFe_xO_y (C/C₀=0.01) and nZnO (C/C₀=0.09) particles are retained in the porous media. However, in the presence of HA, the transport efficiency of nFe_xO_y (C/C₀=0.64) increases significantly. The extensively high amount of nAg and nTiO₂ particles are transported in the absence/presence of HA. The surface charge of particles and thus the interaction energy between the NPs and the sand is the main factor controlling the deposition of NPs. Overall, it could be stated that there is a risk of migration of nAg and nTiO₂ particles irrespective of the presence of organic matter or of nFe_xO_y particles in the presence of organic matter through the aquifer porous media. However, in the natural groundwater system, when the different ion is present, the extent of transport of NPs is expected to be less, and the risk associated with releasing of NPs in the groundwater would be comparatively low than that is predicted under the controlled de-ionized water condition. However, the nTiO₂ particles always have a high risk of release into the groundwater.

鉴于纳米粒子（NPs）具有大量的商业和医学应用，它们的产量已显着增加。在环境中释放这些NP可能会有一定的风险。为了评估NP在地下水中释放的可能风险，重要的是评估NP在多孔介质中的命运和运输行为。因此，本研究的目的是评估广泛使用的NP [即银（Ag），氧化铁（Fe _x O _y），二氧化钛（TiO ₂）和氧化锌（ZnO）]在受控的去离子和天然地下水条件下，在存在和/或不存在有机物[例如腐殖酸（HA）]的情况下通过多孔介质进行渗透。为了实现该目的，首先，在有或没有HA的情况下进行NP的详细表征。使用一维沙填充柱进行柱迁移实验。从色谱柱的一端注入不同的NP，流速为0.0054 cm / sec。结果表明，nAg，nTiO ₂和nZnO颗粒在悬浮液中是胶体稳定的，而nFe _x O _y颗粒趋于迅速聚集和沉降。但是，在存在HA的情况下，nFe _x O _y的胶体稳定性在悬架中明显增加。评估不同金属NP的传输行为表明，大量nFe _x O _y（C / C ₀ = 0.01）和nZnO（C / C ₀ = 0.09）颗粒保留在多孔介质中。但是，在存在HA的情况下，nFe _x O _y（C / C ₀ = 0.64）的传输效率显着提高。大量的nAg和nTiO ₂缺少/存在HA的情况下运输颗粒。颗粒的表面电荷以及NP与沙子之间的相互作用能是控制NP沉积的主要因素。总的来说，可以说存在nAg和nTiO ₂颗粒迁移的风险，而与是否存在有机物或存在于有机物中的nFe _x O _y颗粒通过含水层多孔介质无关。但是，在天然地下水系统中，当存在不同的离子时，NPs的传输范围预计会较小，与地下水中NPs释放相关的风险将比受控条件下预测的相对较低。离子水条件。但是，nTiO ₂ 颗粒物始终具有释放到地下水中的高风险。