Carboxymethyl cellulose/alginate/chitosan-based polyelectrolyte complex hydrogel with irregularly shaped...

Area of Science:

• Materials Science
• Environmental Science
• Nanotechnology

Background:

• Hexavalent chromium (Cr(VI)) poses significant environmental risks in industrial wastewater.
• Developing efficient and scalable remediation technologies is crucial for environmental protection.

Purpose of the Study:

• To develop a novel nanocomposite hydrogel for supporting Pd/Au/Ag/Pt nanowires.
• To investigate the catalytic efficiency of the nanocomposite hydrogel for Cr(VI) reduction.

Main Methods:

• Fabrication of a natural polyelectrolyte complex (PEC) hydrogel using carboxymethyl cellulose, alginate, and chitosan.
• Synthesis of Pd/Au/Ag/Pt nanowires with irregular morphology via galvanic replacement and co-reduction.
• Crosslinking the hydrogel with glutaraldehyde, citric acid, and calcium ions to enhance stability and porosity.
• Incorporation of Pd/Au/Ag/Pt nanowires into the PEC hydrogel matrix to create a nanocomposite material.

Main Results:

• The PEC hydrogel provided a suitable matrix for stabilizing Pd/Au/Ag/Pt nanowires.
• The Pd/Au/Ag/Pt nanowires demonstrated rapid catalytic reduction of Cr(VI) to Cr(III) within 15 minutes in batch tests.
• The nanocomposite hydrogel maintained structural integrity and high catalytic efficiency during continuous-flow operation.
• Complete Cr(VI) removal was achieved within 5 hours of continuous-flow operation.

Conclusions:

• The developed PEC hydrogel nanocomposite is a promising material for the catalytic reduction of Cr(VI) in industrial wastewater.
• The system offers a robust, scalable, and efficient solution for environmental remediation.
• The unique morphology of the nanowires and the properties of the hydrogel contribute to the enhanced catalytic performance.