Non-modified cellulose fibers for toxic heavy metal adsorption from water

Heavy metal pollution poses a considerable environmental threat as toxic substances accumulate in ecosystems, causing prevailing ecological damage and generating risks to human health. We characterized physicochemically unmodified cellulose samples extracted from Ecuadorian biodiversity and used them as potential decontaminants of heavy metal ions in water. The isolated materials underwent characterization using Fourier Transform Infrared Spectroscopy-Attenuated Total Reflectance (FTIR-ATR), X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and X-ray Photoelectron Spectroscopy (XPS). Initial testing of heavy metal adsorption involved 2.0 mmol/L and 10.0 mmol/L copper (Cu²⁺) solutions as models. The results demonstrated a removal percentage of Cu²⁺ ions by non-modified cellulose, reaching up to 88.75 ± 2.49% and 54.96 ± 2.51%, respectively using material F25. Additionally, natural (F25, F27, F28, and OP) and control (C1, C, and Af) celluloses were selected to study the removal of Cu²⁺, Cd²⁺, and Pb²⁺ ions from control isolated metal ion solutions ranging from 1 to 100 mg/L. The findings revealed that samples C, OP, and F25 effectively removed Cu²⁺, Cd²⁺, and Pb²⁺ ions when they were present isolated in solutions at concentrations as high as 30 mg/L. Furthermore, assays with mixed metal ion solutions exhibited promising removal of heavy metal ions using OP + F25. Overall, the results suggest that non-modified cellulose derived from biomass holds potential as a material for effectively removing toxic heavy metal ions from water.

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