Peanut shell biochar for Rhodamine B removal: Efficiency, desorption, and reusability

Area of Science:

• Environmental Science
• Materials Science
• Chemical Engineering

Background:

• Wastewater contamination by synthetic dyes like Rhodamine B (RhB) poses environmental risks.
• Developing cost-effective and sustainable adsorbents for dye removal is crucial for environmental remediation.

Purpose of the Study:

• To synthesize and characterize peanut shell biochar (PSB) for efficient Rhodamine B removal from aqueous solutions.
• To investigate the adsorption mechanism, kinetics, and thermodynamics of RhB onto PSB.

Main Methods:

• Peanut shells were converted into biochar and characterized using FTIR and BET surface area analysis.
• Adsorption experiments were conducted to determine optimal conditions (pH, adsorbent dose) and evaluate removal efficiency.
• Isotherm and kinetic models (Freundlich, Langmuir, etc.) were applied to understand the adsorption process.

Main Results:

• Peanut shell biochar exhibited a high surface area (351.11 m²/g) with abundant functional groups for dye adsorption.
• A maximum RhB removal efficiency of 94.0% was achieved at pH 3 with an adsorbent dose of 0.325 g/L.
• The Freundlich isotherm model best described the adsorption equilibrium, indicating multilayer adsorption.

Conclusions:

• Peanut shell biochar is a highly effective, reusable, and sustainable adsorbent for Rhodamine B removal.
• The adsorption process is spontaneous and exothermic, making PSB an attractive option for industrial wastewater treatment.
• This biochar offers a cost-effective and environmentally friendly solution for dye pollution abatement.