Characterization of nanoscale zero-valent iron supported on granular activated carbon and its application in removal of acrylonitrile from aqueous solution.

In this study, nanoscale zero-valent iron supported on granular activated carbon (NZVI/GAC) was synthesized by liquid-phase reduction of Fe(II) and used to degrade acrylonitrile, to improve the effectiveness of GAC as a pre-treatment for biodegradation. The as-prepared composites were characterized by a scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). NZVI nanoparticles with an average size of 20–80 nm were uniformly dispersed on the surface of GAC, but mainly in the pores. The S BET and total pore volume of NZVI/GAC were 478.7 m 2 /g and 0.522 cm 3 /g, which is about half that of GAC. NZVI/GAC had a remarkable removal capacity for acrylonitrile which resulted from the combined effects of reduction, adsorption and micro-electrolysis by the Fe 0 /GAC system. The infrared spectra indicated that Fe 0 and the Fe 0 /GAC micro-electrolysis system played a significant role in degradation of acrylonitrile. Increased biodegradability of acrylonitrile was achieved by pre-treatment with NZVI/GAC before biological treatment. [ABSTRACT FROM AUTHOR]