This work reveals the As(V) adsorption behaviors onto iron oxide (Fe3O4) nanoparticles modified activated carbon (AC), originally developed from biochar (BC), as a green adsorbent denoted by FAC. Since FAC has abundant surface functional groups and a desired porous structure that is favorable for the removal of As(V) in contaminated water, FAC has greatly enhanced the As(V) adsorption capacity of the original BC. Various methods were employed to characterize the FAC characteristics and adsorption mechanism, including pH_pzc determination, BET specific surface area, elemental analysis (EA), and scanning electron microscopy (SEM). Results show that the AC surface was successfully modified by iron oxide nanoparticles, enhancing the porosity and specific surface area of original adsorbent. Batch adsorption tests indicated a well-fitted Langmuir model and pseudo-second-order model for As(V) adsorption. Additionally, the highest adsorption capacity (Q_max = 32.57 mg/g) by FAC was higher than previously reported literature reviews. Until now, no article was conducted to research the effect of carbon surface chemistry and texture on As removal from waters. It is required to obtain a rational view of optimal conditions to remove As from contaminated water.

中文翻译：

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氧化铁纳米粒子功能化活性炭的合成及其在砷吸附中的应用

这项工作揭示了As（V）在氧化铁（Fe3O4）纳米颗粒改性的活性炭（AC）上的吸附行为，该活性炭最初是由生物炭（BC）开发的，以FAC表示为绿色吸附剂。由于FAC具有丰富的表面官能团和所需的多孔结构，有利于去除污水中的As（V），因此FAC大大增强了原始BC的As（V）吸附能力。采用多种方法表征FAC特性和吸附机理，包括pH _pzc测定，BET比表面积，元素分析（EA）和扫描电子显微镜（SEM）。结果表明，AC表面已被氧化铁纳米颗粒成功修饰，从而提高了原始吸附剂的孔隙率和比表面积。批量吸附测试表明，As（V）吸附具有良好的Langmuir模型和伪二级模型。此外， FAC的最高吸附容量（Q _max = 32.57 mg / g）高于先前报道的文献综述。迄今为止，还没有文章研究碳表面化学和质地对从水中去除As的影响。需要获得最佳条件的合理视图，以从污染水中去除As。