Adsorption and reduction of Cr(VI) from aqueous solution using cost-effective caffeic acid functionalized corn starch
Fenglei Liu1, Shan Hua1, Chao Wang2
1School of Life Science, Shaoxing University, Huancheng West Road 508, Shaoxing, 312000, PR China.
Chemosphere
|April 16, 2021
Summary
A novel bio-adsorbent, dialdehyde corn starch-caffeic acid (DACS-CA), effectively removes hexavalent chromium (Cr(VI)). This DACS-CA material demonstrates high adsorption capacity and a redox mechanism for efficient wastewater treatment.
Area of Science:
- Environmental Chemistry
- Materials Science
- Biotechnology
Background:
- Hexavalent chromium (Cr(VI)) poses significant environmental and health risks.
- Developing efficient and cost-effective adsorbents for Cr(VI) removal is crucial for water remediation.
Purpose of the Study:
- To synthesize and characterize a novel bio-adsorbent (DACS-CA) for Cr(VI) removal.
- To investigate the adsorption mechanism and efficiency of DACS-CA for Cr(VI) from aqueous solutions.
Main Methods:
- Immobilization of caffeic acid (CA) onto dialdehyde corn starch (DACS).
- Characterization using IR, Raman, XPS, and 13C NMR.
- Batch adsorption experiments to determine optimal conditions (pH, temperature, solid-liquid ratio).
- Adsorption isotherm and kinetic studies.
Main Results:
- DACS-CA exhibited a maximum Cr(VI) removal capacity of 96.45 mg/g at pH 3.0, 333 K, and a solid-liquid ratio of 0.2.
- Adsorption followed a monolayer model, with chemisorption as the primary removal mechanism.
- Characterization revealed co-existence of Cr(VI) and Cr(III) on DACS-CA, indicating a redox reaction and immobilization process.
Conclusions:
- DACS-CA is a highly effective bio-adsorbent for Cr(VI) removal from wastewater.
- The removal mechanism involves electrostatic interaction, redox transformation, and immobilization of chromium species.
- This adsorbent shows promise for environmental pollution cleanup applications.
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