Pillai Renjith Rajan, Panickar Radhika, Vaidya Uday, Lungu Claudiu T, Antony Veena B, Thomas Vinoy
Department of Mechanical and Materials Engineering, The University of Alabama at Birmingham, AL 35294, USA.
Department of Materials Science & Engineering, Tuskegee University, Tuskegee, AL 36088, USA.
J Environ Chem Eng. 2025 Jun;13(3). doi: 10.1016/j.jece.2025.116759. Epub 2025 Apr 23.
Heavy metal (HM) pollution poses a significant environmental risk globally, necessitating greener, efficient, and cost-effective remediation strategies. This study investigates low-temperature plasma (LTP) assisted modification of carbon and soy fibers for enhanced HM adsorption, targeting Mn (II) and Cd (II) ions in aqueous media. Carbon and soy fibers, fabricated using a wet-lay process, underwent surface modifications with plasma treatments utilizing various precursors, including 2-mercaptoethanol (MCE), ethylenediamine, acetic acid, and N-vinyl pyrrolidone (VP). Comprehensive characterization before and after plasma treatment, and post-HM adsorption, was performed using Scanning Electron Microscopy (SEM), X-ray Photoelectron Spectroscopy (XPS), and 3D imaging, while plasma density was assessed via Optical Emission Spectroscopy (OES). Atomic Absorption Spectrophotometry (AAS) was used to quantify HM removal from aqueous solutions, with MCE-modified fibers demonstrating the highest adsorption capacities (50 mg/g for Mn and 40 mg/g for Cd). Additional parameter studies highlighted optimal adsorption at 35 °C and pH 7. The findings underscore LTP's potential in enhancing HM adsorption efficiency on natural fibers, an approach with limited prior exploration. This research also addresses crucial challenges in HM remediation, such as improving adsorbent retrieval from environmental matrices and minimizing chemical waste during material processing, underscoring the method's environmental and practical significance.
重金属（HM）污染在全球范围内构成了重大的环境风险，因此需要更环保、高效且具有成本效益的修复策略。本研究调查了低温等离子体（LTP）辅助对碳纤维和大豆纤维进行改性以增强对重金属的吸附，目标是去除水介质中的锰（II）和镉（II）离子。采用湿法成型工艺制备的碳纤维和大豆纤维，利用包括2-巯基乙醇（MCE）、乙二胺、乙酸和N-乙烯基吡咯烷酮（VP）在内的各种前驱体通过等离子体处理进行表面改性。在等离子体处理前后以及重金属吸附后，使用扫描电子显微镜（SEM）、X射线光电子能谱（XPS）和3D成像进行了全面表征，同时通过光发射光谱（OES）评估了等离子体密度。使用原子吸收分光光度法（AAS）对水溶液中重金属的去除量进行了量化，结果表明经MCE改性的纤维具有最高的吸附容量（对锰为50 mg/g，对镉为40 mg/g）。额外的参数研究突出了在35°C和pH值为7时的最佳吸附效果。这些发现强调了低温等离子体在提高天然纤维对重金属吸附效率方面的潜力，而此前对该方法的探索有限。本研究还解决了重金属修复中的关键挑战，例如提高从环境基质中回收吸附剂以及在材料加工过程中尽量减少化学废物，凸显了该方法的环境和实际意义。
