Synthesis and evaluation of palladium-functionalized biochar-supported magnetic nanoparticles for efficient nitro reduction

This study investigated the catalytic activity of the magnetic Fe3O4@Bio-R-Pd (Bio = biochar, R = epichlorohydrin and guanidine) for the reduction of nitro compounds. The structural and magnetic properties of the synthesized nanocatalyst were characterized using a suite of techniques including inductively coupled plasma spectrometry (ICP), vibrating sample magnetometer (VSM), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX), Fourier Transform infrared (FT-IR) spectroscopy, and X-ray diffraction (XRD). The recyclability of the synthesized nanocatalyst was confirmed by its complete reversibility upon testing with a vibrating magnetometer, further supporting its paramagnetic nature. Analysis of the SEM images revealed the presence of spherical magnetite particles within the composite. Using these optimized conditions, various aromatic nitro compounds were successfully reduced in the presence of the Fe3O4@Bio-R-Pd catalyst. The results demonstrate the advantageous properties of the synthesized nanocatalyst, including high product yield, stability and resistance at high temperatures, easy separation from the reaction medium, high efficiency with short reaction times, and economic viability. Notably, the synthesized sample exhibited nearly the same initial efficiency after 5 reuses, indicating almost complete recovery and minimal change in its catalytic activity.