The Zuckerberg Institute for Water Research, Blaustein Institutes for Desert Research , Ben Gurion University of the Negev , Sde Boker Campus , 84990 Israel.
Environ Sci Technol. 2018 Jul 17;52(14):7849-7858. doi: 10.1021/acs.est.8b01226. Epub 2018 Jul 3.
In field applications, mostly in porous media, transport of stabilized nano zerovalent iron particles (nZVI) has never exceeded a few meters in range. In the present study, the transport of Carbo-Iron Colloids (CIC), a composite material of activated carbon as a carrier for nZVI stabilized by carboxymethyl cellulose (CMC), was tested under field conditions. The field site lies within a fractured chalk aquitard characterized by moderately saline (∼13 mS) groundwater. A forced gradient tracer test was conducted where one borehole was pumped at a rate of 8 L/min and CMC-stabilized CIC was introduced at an injection borehole 47 m up-gradient. Two CIC-CMC field applications were conducted: one used high 100% wt CMC (40 g/L) and a second used lower 9% wt loading (∼2.7 g/L). Iodide was injected as a conservative tracer with the CIC-CMC in both cases. The ratio between the CIC-CMC and iodide recovery was 76% and 45% in the high and low CMC loading experiments, respectively. During the low CMC loading experiment, the pumping rate was increased, leading to an additional CIC recovery of 2.5%. The results demonstrate the potentially high mobility of nZVI in fractured environments and the possibility for transport manipulation through the adjustment of stabilizer concentration and transport velocity.
在野外应用中，主要是在多孔介质中，稳定纳米零价铁颗粒（nZVI）的传输范围从未超过几米。在本研究中，测试了 Carbo-Iron 胶体（CIC）的传输，这是一种由活性炭作为载体，羧甲基纤维素（CMC）稳定的 nZVI 的复合材料。该野外场地位于一个具有中度盐度（约 13 mS）地下水的断裂白垩含水层中。进行了强制梯度示踪剂测试，其中一个钻孔以 8 L/min 的速度抽取，在 47 m 上梯度的注入钻孔中引入 CMC 稳定的 CIC。进行了两次 CIC-CMC 野外应用：一次使用高浓度 100%wt CMC（40 g/L），另一次使用低浓度 9%wt 负载（约 2.7 g/L）。两种情况下都将碘化物作为示踪剂与 CIC-CMC 一起注入。在高 CMC 负载实验中，CIC-CMC 和碘化物回收率的比值分别为 76%和 45%。在低 CMC 负载实验中，增加了泵送速率，导致额外的 CIC 回收率为 2.5%。结果表明，nZVI 在断裂环境中具有潜在的高迁移性，并且可以通过调整稳定剂浓度和运输速度来操纵运输。
