Abstract
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.