Swift reduction of 4-nitrophenol by easy recoverable magnetite-Ag/layered double hydroxide/starch bionanocomposite.

The main source of nitroaromatic compounds in nature is anthropogenic activities. In the present report, a facile and green method was employed to fabricate highly efficient catalyst to turn toxic nitrophenols to more safe aminophenols. The Fe3O4/Ag@Ca-Al LDH hybrid (FAL hybrid) was synthesized by the Fe3O4 and Ag nanoparticles supported on layer double hydroxide (LDH) and the bionanocomposite (BNC) of this hybrid and starch was prepared via an in situ growth method. The FAL hybrid and BNC were characterized by different techniques. The reduction reaction of 4-nitrophenol in the presence of these catalysts indicated that both of them have high catalytic activity due to their large numbers of hydroxyl groups as capping agent. The comparison rate kinetics study between 4-nitrophenol and 2-nitrophenol showed that the FALS-BNC has higher potential in the case of the para derivative. Also, catalysts were recovered without difficulty and reused after completion of the reduction reaction.