Fe₃O₄-Carbon-Based Composite Derived from the Charge-Transfer Reaction Using Waste Tea Leaves as the Carbon Precursor for Enhanced Removing of Azocarmine G2, Methyl Violet 2B, Eosin B, and Toluidine Blue from Aqueous Solution

Abstract

Ferric chloride salt (FeCl3) is a typical vacant orbital acceptor that accepts electrons from urea molecules. This donor-acceptor interaction yields a Fe3O4 oxide, which can be used for preparing novel adsorbent material. Activated carbon (AC) materials, derived from biomass precursors and used for environmental remediation, have gained increasing attention owing to their sustainability, eco-friendly nature, ease of fabrication, and cost-effectiveness. Globally, a large amount of consumed tea leaf materials is discarded as solid waste. The present study aimed to reuse consumed tea leaves to generate biomass-derived-ACs and coupling AC with Fe3O4 oxide to generate Fe3O4-carbon-based composite for environmental remediation. The synthesized Fe3O4-carbon-based composite was examined to remove four common organic pollutant dye models from an aqueous solution. The effects of several parameters on the adsorption capacity of the synthesized composite were analyzed, and equilibrium data were examined. We found that the synthesized composite displayed promising adsorption activity against the investigated dyes.

Keywords

• charge-transfer interaction
• vacant <i>orbital</i> acceptor
• tea leaf waste
• adsorption of dyes