Noncovalently functionalized carbon nanotubes immobilized Fe–Bi bimetallic oxides as a heterogeneous nanocatalyst for reduction of nitroaromatics

Abstract A novel oCNT-Chitosan-xFe 2 O 3 ⋅yBi 2 O 3 nanocomposite has been synthesized as a catalyst for the reduction of nitroarenes to afford corresponding anilines. This catalyst exhibits excellent efficiency and high chemoselectivity towards varieties of nitro-compounds by using hydrazine hydrate as the reductant, and this magnetically separable nanocatalyst can be used for more than ten cycles. The synergy between iron and bismuth gives the catalyst competitive activity towards precious metallic catalyst, and the active sites are immobilized on the chitosan noncovalently functionalized oxidized carbon nanotubes gives the catalyst long life time. Furthermore, this heterogeneous catalyst was used in a continuous-flow processing by filling up it into a packed bed reactor. It was used for more than 1000 min without any loss of catalytic activity in a scaled-up reduction of p -nitrophenol with a productivity of 0.5 mmol min − 1 .