Nano-scale zero-valent iron (nZVI) has shown its promising treatment technique to decontaminate nitrate from water. However, research reports lack the treatment and regeneration of the spent reagent from the treatment process. This research utilized different derivatives of nZVIs in the purpose of nitrate treatment in its aqueous solution to show their different reactivities in applied batch experiments. Selected nanoparticles were investigated via transmission electron microscopy, surface characterization analyzer, X-ray diffraction and laser-scattering particle size analyzer. The fresh synthesized nZVI had the highest performance with complete nitrate removal within 60 min. Treated nZVI succeeded to regain the lost reactivity of aged nZVI and boosted its removal efficiency 10 times. On the other hand, the regenerated nZVI, recovered from spent synthesized nanoparticles, regained full and complete removal efficiency of nitrate, the same as the synthesized nZVI. The obtained result gives a great competitiveness of nZVI reagent to treat nitrate against any other treatment technology.
Keywords: nitrate removal, nano-scale zero-valent iron, regeneration.