Adsorption of Rubidium/Cesium From Aqueous Solution Using Silane-Modified Prussian Blue-Based Composites.

Area of Science:

• Materials Science
• Environmental Chemistry
• Nanotechnology

Background:

• Prussian blue (PB) is a known adsorbent for alkali metal ions.
• Developing stable and efficient PB-based adsorbents for rubidium (Rb+) and cesium (Cs+) extraction remains a challenge.
• Surface modification is crucial for enhancing adsorbent properties.

Purpose of the Study:

• To synthesize and characterize a novel silane-modified Prussian blue-based composite (PB-Si) adsorbent.
• To evaluate the efficiency of PB-Si for extracting rubidium (Rb+) and cesium (Cs+) ions from aqueous solutions.
• To investigate the adsorption mechanism, kinetics, and regeneration performance of the PB-Si adsorbent.

Main Methods:

• Synthesis of PB-Si adsorbent using Pickering high internal phase emulsion polymerization.
• Modification of Prussian blue with 3-aminopropyl trimethoxy silane.
• Adsorption experiments to determine kinetics, isotherms, and regeneration capacity.
• Analysis of adsorption mechanisms using surface chemistry principles.

Main Results:

• The PB-Si adsorbent achieved rapid adsorption equilibrium within 2.5-3 hours.
• High adsorption capacities were observed: 317.4 mg/g for Rb+ and 402.6 mg/g for Cs+.
• The adsorbent retained significant capacity after five adsorption-desorption cycles (88.3% for Rb+, 91.7% for Cs+).

Conclusions:

• Silane modification enhances the hydrophilicity and stability of Prussian blue composites.
• PB-Si demonstrates excellent performance for Rb+ and Cs+ extraction from aqueous solutions.
• The adsorbent's regenerability and high capacity suggest potential for environmental remediation and resource recovery.