The influence of activated carbon support on nitrate reduction by Fe(0) nanoparticles

Activated Carbon supported Fe(0) nanoparticles (AC-Fe(0)) were applied to the reductive removal of nitrate to investigate the effects of AC support on the reactivity of Fe(0) nanoparticle. XRD, SEM and EDS, XPS analyses on AC-Fe(0) revealed that AC-Fe(0) is more susceptible to oxidation compared to the unsupported Fe(0) nanoparticles, and that the extent of oxidation of the AC-Fe(0) particles will vary depending on the ratios of AC to Fe(0). Nitrate reduction rate of AC-Fe(0) was much slower than that of unsupported Fe(0) nanoparticles. AC-Fe(0) (0.5: 1) particles reduced the nitrate to ca. 40% of the initial concentration, and AC-Fe(0) (5: 1) particles performed poorly with only 10% removal of the nitrate. Besides the deactivation of AC-Fe(0) due to corrosion of Fe(0), the mass transport limitation caused by the thick layering of Fe(0) on porous AC seemed to be another negative factor for the decreased reactivity of AC-Fe(0).