Superparamagnetic Multifunctionalized Chitosan Nanohybrids for Efficient Copper Adsorption: Comparative Performance,...

Area of Science:

• Environmental Science
• Materials Science
• Chemistry

Background:

• Copper (Cu(II)) pollution poses significant environmental and health risks.
• Developing efficient adsorbents for selective copper removal is crucial.
• Magnetic chitosan nanohybrids offer potential for water remediation due to their unique properties.

Purpose of the Study:

• To synthesize and characterize novel magnetic chitosan nanohybrid derivatives for selective Cu(II) adsorption.
• To evaluate the adsorption performance, kinetics, and selectivity of these nanohybrids.
• To investigate the relationship between adsorbent properties and copper adsorption using QSAR models.

Main Methods:

• Synthesis of magnetic chitosan nanohybrids (r-MCS) via co-precipitation of ferroferric oxide (Fe3O4) within chitosan.
• Multifunctionalization of r-MCS with amine and amino acid moieties (TA, A, C, S types).
• Characterization using XPS and FTIR; adsorption studies under varying conditions; kinetic and isotherm modeling; QSAR analysis.

Main Results:

• Functionalized nanohybrids exhibited significantly higher Cu(II) adsorption capacities than the base r-MCS, with TA-type showing the highest capacity (3.29 mmol.Cu.g-1).
• Adsorption followed Langmuir and pseudo-second-order models, indicating favorable interactions and fast kinetics (mostly endothermic, except TA-type).
• The nanohybrids demonstrated selective Cu(II) adsorption from multicomponent solutions and high durability (>93% desorption efficiency over six cycles).

Conclusions:

• Functionalized magnetic chitosan nanohybrids are effective, selective, and reusable adsorbents for Cu(II) removal.
• The study provides insights into adsorption mechanisms and establishes quantitative structure-activity relationships for adsorbent design.
• These materials offer a sustainable solution for mitigating copper pollution in aquatic environments.