Water pollution caused by organic dyes is a critical environmental issue.Although activated carbon(AC)is commonly used for dye adsorption,its effectiveness is limited by challenges in separation and regeneration.To ad...Water pollution caused by organic dyes is a critical environmental issue.Although activated carbon(AC)is commonly used for dye adsorption,its effectiveness is limited by challenges in separation and regeneration.To address these limitations,a convenient recyclable magnetic activated carbon(MAC)was fabricated via co-precipitation and calcination method,serving as adsorbent and catalyst for methyl orange(MO)removal through a Fenton-like degradation process.Characterization techniques,including XRD,FTIR,SEM and TEM,confirmed that Fe_(3)O_(4) nanoparticles(10–20 nm)were uniformly dispersed on AC surface.The MAC maintaining a high surface area(997 m^(2)/g)and pore volume(0.795 cm^(3)/g)and exhibited superparamagnetic properties with a saturated magnetization of 5.52 emu/g,enabling effective separation from aqueous solutions by magnet.Batch adsorption studies revealed that MO adsorption onto MAC followed pseudo-second-order kinetic and Freundlich isotherm model,with a maximum adsorption capacity of 205 mg/g at 25℃.Thermodynamic analysis showed that the adsorption process was spontaneous and endothermic.Simultaneous degradation of MO and in-situ regeneration of MAC were achieved via Fenton-like reaction using sodium persulfate(PS).Under a PS concentration of 9 mmol/L,the MO removal efficiency near 95%after 60 min,with a total organic carbon(TOC)reduction of 83.1%.The reaction of Fe_(3)O_(4) and oxygen functional groups on AC surface with PS facilitated the generation of SO_(4)^(·-),thereby enhancing catalytic degradation of MO.The degradation efficiency improved as the temperature increased from 25℃ to 45℃.Cycle tests demonstrated that the MO removal efficiency of MAC remained above 90%after 5 cycles of regeneration.Overall,this study highlights the potential of MAC for efficient removal of organic dyes from water through the coupling of adsorption and Fenton-like degradation,providing a promising solution for addressing water pollution challenges.展开更多
基金supported by the National Key Research and Development Program of China(grant No.2022YFC3701900)the National Natural Science Foundation of China(grant No.22278423,U21A20316)the Science Foundation of China University of Petroleum,Beijing(grant No.2462021QNXZ007).
文摘Water pollution caused by organic dyes is a critical environmental issue.Although activated carbon(AC)is commonly used for dye adsorption,its effectiveness is limited by challenges in separation and regeneration.To address these limitations,a convenient recyclable magnetic activated carbon(MAC)was fabricated via co-precipitation and calcination method,serving as adsorbent and catalyst for methyl orange(MO)removal through a Fenton-like degradation process.Characterization techniques,including XRD,FTIR,SEM and TEM,confirmed that Fe_(3)O_(4) nanoparticles(10–20 nm)were uniformly dispersed on AC surface.The MAC maintaining a high surface area(997 m^(2)/g)and pore volume(0.795 cm^(3)/g)and exhibited superparamagnetic properties with a saturated magnetization of 5.52 emu/g,enabling effective separation from aqueous solutions by magnet.Batch adsorption studies revealed that MO adsorption onto MAC followed pseudo-second-order kinetic and Freundlich isotherm model,with a maximum adsorption capacity of 205 mg/g at 25℃.Thermodynamic analysis showed that the adsorption process was spontaneous and endothermic.Simultaneous degradation of MO and in-situ regeneration of MAC were achieved via Fenton-like reaction using sodium persulfate(PS).Under a PS concentration of 9 mmol/L,the MO removal efficiency near 95%after 60 min,with a total organic carbon(TOC)reduction of 83.1%.The reaction of Fe_(3)O_(4) and oxygen functional groups on AC surface with PS facilitated the generation of SO_(4)^(·-),thereby enhancing catalytic degradation of MO.The degradation efficiency improved as the temperature increased from 25℃ to 45℃.Cycle tests demonstrated that the MO removal efficiency of MAC remained above 90%after 5 cycles of regeneration.Overall,this study highlights the potential of MAC for efficient removal of organic dyes from water through the coupling of adsorption and Fenton-like degradation,providing a promising solution for addressing water pollution challenges.
