Preparation of NH2-MIL-125/BiOBr composite and study on its photocatalytic degradation of xanthate

NI Chao; LUAN Jianfu; LIU Jiayou; WANG Teng; ZHANG Kefei; YU Hesheng

doi:10.13247/j.cnki.jcumt.20240500

Abstract：To achieve efficient xanthate removal from mineral processing wastewater,a novel MOF/BOB composite photocatalytic material(NM/BOB)was synthesized by combining the metal-organic framework(MOF)material NH2-MIL-125(NM-125)with BiOBr(BOB)via solvothermal synthesis.The physical phase,morphology,and photoelectrochemical properties of NM/BOB were characterized by X-ray diffraction(XRD),Fourier-transform infrared spectroscopy(FTIR),scanning electron microscopy(SEM),and electrochemical impedance spectroscopy(EIS).Photocatalytic degradation of sodium isobutyl xanthate(SIBX)using NM/BOB was evaluated,and the mechanisms behind SIBX degradation were explored.Results indicate that the uniform distribution of NM-125 on BOB sheets enhances the specific surface area of BOB and increases active sites,thereby facilitating SIBX degradation.Under the optimized conditions(400 mg/L catalyst dosage,200 mg/L SIBX concentration,pH=7.0～7.5,and 150 min irradiation),the SIBX degradation efficiency reaches 99.09％.Notably,NM/BOB exhibits good stability,maintaining a degradation efficiency of 81％and beyond after four consecutive cycles.Neither solution pH nor Ca2+/Mg2+ions exhibit significant effects on the degradation process.Compared to the individual components(NM-125 and BOB),NM/BOB establishes a type-Ⅱ heterojunction,promoting photogenerated electron-hole pair separation while suppressing carrier recombination.This mechanism predominantly accounts for the enhanced photocatalytic efficiency.