Preparation and Characterization of Magnetic Biochar Nanocomposites via a Modified Solvothermal Method and Their Use as Efficient Heterogeneous Fenton-like Catalysts
Yuting Tu, Zhiping Peng, Jichuan Huang, Xuena Wu, Lingjun Kong, Zhixiong Liang, Linxiang Yang, Zhijun Lin
Abstract
In this study, magnetic biochar nanocomposites (FeC–S) were prepared by employing ethylene glycol as a liquefaction agent of corn stalks and solvent for the solvothermal synthesis approach. The effects of urea/Fe3+ molar ratio, final solvothermal temperature, and residence time on the properties of FeC–S were investigated. Magnetic biochar synthesized through pyrolysis and the chemical co-precipitation method (FeC–P) was employed for comparison. As revealed by Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy/energy-dispersive X-ray spectrometry, vibrating sample magnetometer analysis, and Fenton-like oxidation of sulfamethoxazole, the impregnated iron in FeC–S presented as Fe3O4 nanoparticles with an average grain size of 8.9 nm, which makes the material magnetically separable. The FeC–S exhibited a higher Fenton-like catalytic activity than FeC–P, due to the highly dispersed and smaller crystalline size of loaded Fe3O4 particles, as well as the higher amount of oxygen-containing functional groups. The stability test showed that FeC–S can be easily recycled for five subsequent runs without significant activity loss.