(549a) Procyanidin-Assisted Synthesis of Fe-Pd Nanoparticles for Superior Dechlorination of p-Chlorophenol

Nanoscale zero-valent iron has been widely applied in environmental remediation and toxic waste treatment. However, the dechlorination activity of Fe nanoparticles can be impeded by the iron hydroxides formed during the reaction. In this study, Fe-Pd nanoparticles (NPs) were synthesized and stabilized by procyanidin with superior dechlorination towards p-chlorophenol which can relieve the effect of the iron hydoxides. The prepared Fe-Pd NPs were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). Fourier transform infrared (FTIR) spectroscopy was used to investigated the interaction of Fe-Pd NPs and ferrous ions in the presence of procyanidin. The synthesized Fe-Pd NPs performed pseudo first order reaction rate constant. Increasing the amount of procyanidin in the synthesis of Fe-Pd NPs greatly enhanced the dechlorination activity, which may not only attribute to the homogeneous distribution of Fe-Pd NPs, but also attribute to the interaction of ferrous ions and procyanidin. The presence of procyanidin was found to avoid the aggregation of Fe-Pd NPs. Moreover, the formation of ferrioxyhydroxide on the surface of Fe-Pd NPs, which restricts the mass transfer and covers the active sites of Fe-Pd NPs, was also prevented by procyanidin. This strategy of the suppression of the formation of iron hydroxides on the surface of Fe-Pd NPs may be further applied to the recycling of Fe during the dechlorination.