Biosorption of malachite green by eggshells: mechanism identification and process optimization

Area of Science:

• Environmental Science
• Materials Science
• Chemical Engineering

Background:

• Wastewater contamination by synthetic dyes like malachite green poses significant environmental risks.
• Developing cost-effective and sustainable methods for dye removal is crucial for water remediation.

Purpose of the Study:

• To investigate the efficacy of waste eggshells as a biosorbent for malachite green dye removal.
• To elucidate the biosorption binding mechanism using advanced characterization techniques.
• To optimize the biosorption process using Response Surface Methodology (RSM).

Main Methods:

• Biosorption experiments using waste eggshells and malachite green dye.
• Optimization of biosorption parameters via Response Surface Methodology (RSM) with Box-Behnken Design.
• Characterization of eggshell biosorbent before and after dye adsorption using SEM, XRD, BET, and FTIR.

Main Results:

• Eggshells demonstrated significant potential for removing malachite green dye from wastewater.
• The biosorption mechanism involved a combination of physical adsorption, alkaline fading, and microprecipitation.
• RSM analysis provided quantitative relationships between process variables and dye removal efficiency.

Conclusions:

• Waste eggshells are a viable, inexpensive, and effective biosorbent for malachite green dye removal.
• The study provides insights into the biosorption mechanism, aiding in the design of efficient wastewater treatment systems.
• Utilizing waste eggshells aligns with principles of circular economy and sustainable environmental management.