use of nano supported nickel catalyst in reduction of p-nitrophenol using hydrazine hydrate as hydrogen donor

ABSTRACT

P-aminophenol was prepared by reduction of p-nitro-pheilol over nano sized nickel catalysts supported on two different supports, SiO2 and AI2O3 using hydrazine hydrate as hydrogen source. Several loadings of nano-sized Ni were used thus, 20, 5, and 2.5 wt% were prepared. XRD and ESR were employed to investigate the prepared catalysts. The Ni/AI2O3 support was found to be more effective and gives high durability. The catalytic activity of the reaction was found to be influenced by the crystallinity of the nickel in addition to the strain between nano sized nickel particles. The catalytic activity of the prepared catalysts was compared with commercial Raney nickel and showed higher activity especially at lower loading. During the reaction a detectable change of the color was observed from yellow to green to colorless, which enables us to propose a mechanism of this reaction