Enhanced removal of Cr(VI) using a modified environment-friendly adsorbent

Area of Science:

• Environmental Chemistry
• Materials Science
• Adsorption Technology

Background:

• Chromium(VI) is a toxic pollutant requiring efficient removal methods.
• Chitosan (CS) is a promising biomaterial for adsorption but can be further functionalized.
• Modification of chitosan with ferric chloride (FeCl3·6H2O) and sodium laurylsulfonate (SLS) can enhance its adsorption properties.

Purpose of the Study:

• To synthesize and characterize a novel adsorbent, CS-Fe-SLS.
• To investigate the adsorption performance of CS-Fe-SLS for Cr(VI) removal.
• To evaluate the influence of various parameters on Cr(VI) adsorption.

Main Methods:

• Synthesis of CS-Fe-SLS through modification of chitosan.
• Adsorption experiments to determine optimal pH, time, and concentration.
• Analysis of coexisting ion effects and material characterization using SEM, FTIR, and XRD.

Main Results:

• Optimal adsorption conditions: pH 3.0, 120 min equilibrium time.
• Maximum adsorption capacity of 131.91 mg/g, indicating single and multi-layer adsorption.
• CS-Fe-SLS showed enhanced adsorption compared to chitosan, with Cr(VI) reduction to Cr(III) occurring.

Conclusions:

• CS-Fe-SLS is an effective adsorbent for Cr(VI) removal.
• Adsorption mechanism involves physical and chemical processes, linked to -NH and -OH groups.
• The modified chitosan exhibits improved morphological and adsorption characteristics for heavy metal remediation.