Due to its low toxicity and high reactivity, nanoscale zero-valent iron (nZVI) is widely used as a remediation agent. However, nZVI is also prone to rapid aggregation and surface oxidation, which significantly reduces its practical efficacy. Here three enhancement techniques, proposed to overcome these limiting factors, incremental addition, pH adjustment and the application of ultrasonic energy, were systematically evaluated for their ability to increase the remediation efficiency of 1,1,1-Trichloro-2,2-bis(4-chlorophenyl)ethane (DDT) sorbed onto the surface of a soil surrogate. The efficacy of nZVI was also compared to the effectiveness of microscale zero valent iron (μZVI). Of the three enhancement techniques studied, only ultrasonic energy significantly enhanced the effectiveness of nZVI for the degradation of DDT and its primary degradation products due to disaggregation and surface cleaning of nZVI and increased ultrasound induced mixing. While pH had no effect on the degradation efficiency of nZVI, low pH significantly enhanced the effectiveness of μZVI remediation. This was attributed to the sustained low solution pH reducing surface corrosion products, increasing surface area and maintaining a cationic surface for attracting anionic DDT.

由于其低毒性和高反应活性，纳​​米级零价铁（n ZVI）被广泛用作修复剂。然而，n ZVI也易于快速聚集和表面氧化，这大大降低了其实际功效。在这里，系统地评估了三种克服这些限制因素的增强技术，即增加添加量，调节pH值和应用超声能量，以提高其提高1,1,1-Trichloro-2,2-bis（ 4-氯苯基）乙烷（DDT）吸附到土壤替代物的表面。n的功效还将ZVI与微型零价铁（μZVI）的有效性进行了比较。在研究的三种增强技术中，由于n ZVI的分解和表面清洁以及超声感应混合的增加，只有超声能量显着增强了n ZVI对DDT及其主要降解产物降解的有效性。pH值对n ZVI的降解效率没有影响，而低pH值则显着提高了μZVI修复的效率。这归因于持续的低溶液pH值降低了表面腐蚀产物，增加了表面积并保持了阳离子表面以吸引阴离子DDT。