Recently, nanoscale zero-valent iron (NZVI) has been proposed
as a potential reductant because of its high specific surface area
and great capacity for reductive reaction, especially for halogenated
organic contaminants [11,12]. Nevertheless, there are technical
challenges for practical applications. For example, NZVI was
easily agglomerated and may be oxidized rapidly by oxidative species
in ambient conditions [12].When the Fe0 surface is blocked by
oxide precipitates, the activity of NZVI could be seriously hindered,
leading to a decrease of reaction rate and efficiency. To overcome
the above disadvantages, immobilization of NZVI onto a support
(AC, metallic oxide, zeolite etc.) has been regarded as an effective
approach [13,14]. In this work, we chose activated carbon (AC)
because it has been widely applied in treating organic pollutants
[15].