Neodymium and Yttrium Adsorption on Citrate-Modified Cellulose: Experimental and Computational Insights

Area of Science:

• Materials Science
• Environmental Chemistry
• Rare Earth Element Separation

Background:

• Rare earth elements (Neodymium and Yttrium) are critical for modern technologies.
• Separating Nd and Y is challenging, with solvent extraction being the dominant but environmentally taxing method.
• Adsorption offers a sustainable and cost-effective alternative for rare earth element recovery.

Purpose of the Study:

• To evaluate cellulose citrate (CC) as an adsorbent for Yttrium (Y) and Neodymium (Nd) removal.
• To investigate the adsorption mechanism using experimental and computational methods.
• To explore a green synthesis approach for cellulose citrate from Spartium junceum.

Main Methods:

• Green synthesis of cellulose citrate from raw cellulose and citric acid.
• Experimental adsorption studies varying contact time, pH, and metal concentration.
• Computational modeling using Density Functional Theory (DFT) and Molecular Mechanics (MM) simulations.

Main Results:

• Cellulose citrate demonstrated high efficiency in adsorbing both Y and Nd.
• Adsorption is pH-dependent, reaching equilibrium around 60 minutes.
• Selectivity varied: Y preferred at lower concentrations, Nd at higher concentrations, with notable Nd selectivity below pH 3.
• DFT and MM simulations corroborated experimental findings and elucidated the adsorption mechanism.

Conclusions:

• Cellulose citrate is a promising, eco-friendly adsorbent for Y and Nd separation.
• The study provides mechanistic insights into rare earth element adsorption on functionalized cellulose.
• This research supports sustainable practices in rare earth element recovery and recycling.