Preparation of biochar-metal organic framework composite by one-pot method for the adsorption of perfluorooctanoic acid

A novel biochar-metal organic framework composite material (MIL-101(Fe)@BC) was prepared using the one-pot method. The material was characterized using Fourier-transform infrared spectroscopy, scanning electron microscopy, and nitrogen adsorption-desorption analysis. The adsorption efficiency and mechanism of MIL-101(Fe)@BC to perfluorooctanoic acid (PFOA) were investigated and compared with five commonly used engineering carbon materials. The results showed that MIL-101(Fe)@BC achieved optimal adsorption at pH 4, with an optimum dosage of 0.05 g/L within 1 h. The adsorption isotherm of PFOA on MIL-101 (Fe)@BC followed both Langmuir and Freundlich models, with a maximum saturation adsorption capacity of 925.93 µmol/g. The adsorption process followed pseudo-second-order kinetics, and pore filling and hydrogen bonding were identified as the main adsorption mechanisms of MIL-101(Fe)@BC to PFOA. MIL-101(Fe)@BC exhibited superior adsorption and regeneration efficiency compared to widely used engineering carbon materials, indicating significant practical application potential. © 2024, Youke Publishing Co.,Ltd. All rights reserved.