In this study, iron nanoparticles impregnated hydrochar (FeNPs@HC) was synthesized using lignocellulosic waste and simple one-pot synthetic method. During hydrothermal carbonization (HTC) process, the mixture of lignocellulosic waste and ferric nitrate (0.1~0.5 M) as a precursor of iron nanoparticles was added and heated to 220^oC for 3 h in a teflon sealed autoclave, followed by calcination at 600°C in N₂ atmosphere for 1 h. For the characterization of the as-prepared materials, X-ray diffraction (XRD), cation exchange capacity (CEC), fourier transform infrared spectrometer (FT-IR), Brunauer-Emmett-Teller (BET), transmission electron microscope (TEM), Energy Dispersive X-ray Spectroscopy (EDS) were used. The change of Fe(III) concentration in the feedstock influenced characteristics of produced FeNPs@HC and removal efficiency towards As(V) and Pb(II). According to the Langmuir isotherm test, maximum As(V) and Pb(II) adsorption capacity of Fe_0.25NPs@HC were found to be 11.81 and 116.28 mg/g respectively. The results of this study suggest that FeNPs@HC can be potentially used as an adsorbent or soil amendment for remediation of groundwater or soil contaminated with arsenic and cation heavy metals.

Keywords: Lignocellulosic waste, Biochar, Hydrochar, Iron Nanoparticles, One-pot synthesis