Selective solid phase extraction of lanthanides from tap and river waters with ion imprinted polymers

Area of Science:

• Materials Science
• Analytical Chemistry
• Separation Science

Background:

• Selective extraction of lanthanides is crucial for various applications.
• Existing methods often lack simultaneous selectivity for all lanthanides.
• Development of efficient and selective ion-binding materials is an ongoing challenge.

Purpose of the Study:

• To synthesize and characterize a novel ion imprinted polymer (IIP) for simultaneous selective extraction of all lanthanide ions.
• To evaluate the performance of the IIP in solid phase extraction (SPE) for lanthanides.
• To assess the potential of the IIP for real-world applications in water analysis.

Main Methods:

• Synthesis of an ion imprinted polymer (IIP) using Nd3+ as a template ion, methacrylic acid, and ethylene glycol dimethacrylate in acetonitrile.
• Synthesis of a non-imprinted polymer (NIP) as a control.
• Packing of IIP particles into SPE cartridges for selective lanthanide extraction.
• Optimization of SPE conditions (percolation, washing, elution) for selectivity and recovery.
• Evaluation of extraction recoveries, selectivity against interfering ions, capacity, and breakthrough volume.
• Testing the IIP for lanthanide extraction from spiked tap and river water samples.

Main Results:

• The synthesized IIP demonstrated selective and simultaneous extraction of all tested lanthanide ions.
• Extraction recoveries for eight lanthanides averaged 83% with the IIP, compared to 14-36% with the NIP.
• Interfering ions from alkali, transition, and post-transition metal families showed <3% extraction with the IIP.
• The IIP exhibited a specific capacity of 9 mg Nd3+ per gram (60 μmol g-1) and a breakthrough volume of 1 mL per mg IIP.
• An enrichment factor of 15 was achieved, allowing both selective extraction and concentration of lanthanides.
• The IIP was successfully applied to extract lanthanides from spiked tap and river water samples.

Conclusions:

• A novel IIP has been successfully synthesized for the simultaneous and selective extraction of all lanthanide ions.
• The developed SPE method using IIP offers high efficiency, selectivity, and capacity for lanthanide separation.
• The IIP shows significant potential for the preconcentration and analysis of lanthanides in environmental water samples.