Silsesquioxane-crosslinked chitosan aerogels with highly selective adsorption for Au(III)

Area of Science:

• Materials Science
• Nanotechnology
• Environmental Chemistry

Background:

• Silsesquioxanes are versatile precursors for advanced materials.
• Chitosan-based aerogels offer porous structures for adsorption.
• Efficient gold recovery from solutions remains a significant challenge.

Purpose of the Study:

• To synthesize a novel water-soluble silsesquioxane precursor (DEA-GSQ).
• To prepare and characterize chitosan-based hybrid aerogels (DGCA) using DEA-GSQ.
• To evaluate the adsorption performance of DGCA for Au(III) removal.

Main Methods:

• Nucleophilic substitution reaction for DEA-GSQ synthesis.
• Crosslinking of chitosan with DEA-GSQ to form DGCA hybrid aerogels.
• Comprehensive characterization using FTIR, XRD, TGA, SEM, compression testing, and MIP.
• Adsorption experiments to determine Au(III) capacity and kinetics.

Main Results:

• The DGCA hybrid aerogel exhibited selective adsorption for Au(III).
• Saturated adsorption capacity reached 918.16 mg/g at pH 6.
• Adsorption kinetics were well-described by pseudo-second-order and Langmuir models.
• Au(III) was reduced to Au(0) via the CN bond during adsorption.

Conclusions:

• The developed DGCA hybrid aerogel is highly effective for Au(III) adsorption.
• The material demonstrates potential for practical gold recovery.
• The study provides a foundation for designing adsorption devices for Au(III) removal.