One-pot fabrication of magnetic biochar by FeCl₃-activation of lotus seedpod and its catalytic activity towards degradation of Orange G

Abstract

An advanced magnetic biochar (MBC) was facilely prepared via one-pot FeCl3-activation of lotus seedpod. Simultaneous carbonization, activation, and magnetization formed magnetic Fe3O4 nanoparticles and nanowires over the biochar base. The specific surface area (SBET) and the total pore volume (Vtotal) of MBC were 349 m2/g and 0.31 cm3/g, which were 2.0-fold and 3.9-fold higher than those of biochar, respectively. In addition, the saturation magnetization of MBC reached 6.94 emu/g, which could facilitate its magnetic separation and recovery. In heterogeneous Fenton-like catalytic oxidation, 0.40 g/L MBC decolorized 100% Orange G and reduced 58% COD by 350 ppm H2O2 within 120 min. The degradation kinetics were calculated with different MBC samples and reactions followed pseudo-first-order kinetics with the highest rate constant of 0.034 min-1. Moreover, catalytic activity dropped by only 6.4% after four reuse cycles, with negligible iron leaching. Based on these results, MBC could be a low-cost, highly effective, and relatively stable catalyst for treating Orange G in wastewater.

Simple One-Step Synthesis of Nipa Frond-Derived Magnetic Porous Carbon for Decolorization of Acid Yellow 23

“…As reported in the literature [35,36,52], diferent Fe-based particles could be generated during the pyrolysis of FeCl 3 -loaded biomass as follows:…”

“…However, when the FeCl 3 /NF mass ratio was increased from 0.1 to 0.2, the trend was reversed. According to Do et al [36], the lack of water released from the biomass carbonization at high ratios may suppress the conversion of FeCl 3 to Fe 3 O 4 . Table 1 reveals that the pyrolysis efciency improved as the FeCl 3 / NF mass ratio increased.…”

“…On the other hand, the carbon support can fx magnetic particles and prevent their aggregation into bigger particles [20,34]. Overall, the advanced MPC combines desirable physicochemical properties, including the porous structure and functional groups of carbon supports, as well as the magnetic separability and catalytic activity of Fe-based particles [35][36][37].…”

“…According to Bedia et al [41], FeCl 3 -activation of biomass yields MPC with well-developed porosity and welldispersed iron-based particles. Do et al [36] proved that MPC prepared via one-step pyrolysis showed high catalytic activity, long reusability, and good stability in the Fentonlike treatment of Orange G. In spite of this, there are still few reports on MPC fabricated through FeCl 3 -activation of biomass resources for use in catalysis. Further research on AY23 treatment to explore MPC catalysts is necessary.…”

“…It is found that FeCl 3 -activation of various biomass resources can yield MPCs with a diversity of porous structures, functional groups, and iron-based products which signifcantly afect their magnetic properties, adsorption capacities, and catalytic activities [22,36,42]. To expand the selection of MPC for further applications, increased research on the fabrication conditions, properties, and catalytic performance of MPC from newly prospective biomass resources is desired.…”