Abstract:
In this study, magnetic biochar was synthesized by doping Fe3O4 onto the biochar surface followed by analysis of its properties. The efficiency of methylene blue (MB) removal through the combined processes of adsorption and photolysis was assessed. The presence of Fe3O4 on the biochar surface was confirmed using Raman spectroscopy and X-ray photoelectron spectroscopy. The magnetic biochar, after MB adsorption, showed a magnetism of 39.50 emu/g leading to a 97.07 % recovery rate. The specific surface area of biochar was higher (380.68 m2/g) than that of magnetic biochar (234.46 m2/g), and the maximum adsorption capacity of MB was higher in the biochar (0.03 mg/g) than that in magnetic biochar (0.02 mg/g) under the optimal conditions for MB adsorption. The MB adsorption experiments using biochar or magnetic biochar were optimally conducted under 10-20 mg/L MB concentration, 1 g biochar dosage, pH 12, 200 rpm rotation speed, 25 °C temperature, and 30 min duration. Under dark conditions, biochar had a higher MB removal rate, at 83.91 %, compared to magnetic biochar, at 78.30 %. Under visible light (λ > 425 nm), magnetic biochar effectively removed MB within 10 min, highlighting the synergistic effect of adsorption and photolysis. MB is physically and chemically adsorbed by the monolayer on the surface of EB and EMB according to adsorption behavior.
摘要:
在这项研究中,通过在生物炭表面掺杂Fe3O4合成磁性生物炭,然后分析其性能。评估了通过吸附和光解组合过程去除亚甲基蓝(MB)的效率。使用拉曼光谱和X射线光电子能谱证实了生物炭表面上Fe3O4的存在。磁性生物炭,MB吸附后,表现出39.50emu/g的磁性,回收率为97.07%。生物炭的比表面积(380.68m2/g)高于磁性生物炭(234.46m2/g),在最佳吸附条件下,生物炭对MB的最大吸附量(0.03mg/g)高于磁性生物炭对MB的最大吸附量(0.02mg/g)。使用生物炭或磁性生物炭的MB吸附实验在10-20mg/LMB浓度下进行。1克生物炭用量,pH值12,转速200转/分,温度25°C,和30分钟的持续时间。在黑暗条件下,生物炭具有较高的MB去除率,83.91%,与磁性生物炭相比,78.30%。在可见光下(λ>425nm),磁性生物炭在10分钟内有效去除MB,突出了吸附和光解的协同作用。根据吸附行为,MB被单层物理和化学吸附在EB和EMB的表面上。