# Functionalized poly(glycidylmethacrylate) for selective uranium(vi) adsorption: experimental and theoretical calculation insights

## TL;DR

A new material is developed to selectively capture uranium from acidic solutions, showing high efficiency and reusability.

## Contribution

A novel functionalized PGMA adsorbent with polyamine-phosphonic acid is introduced for selective uranium recovery.

## Key findings

- PPA-PGMA achieved a high uranium adsorption capacity of 0.828 mmol g−1 under optimal pH conditions.
- The adsorbent maintained 88–90% efficiency over six reuse cycles using NaHCO3 for desorption.
- The material showed selectivity for uranium over iron and silicon in acidic ore leachates.

## Abstract

This study investigates the recovery of uranium(vi) using a novel functionalized polyglycidyl methacrylate (PGMA) adsorbent, PPA-PGMA, modified with polyamine-phosphonic acid. The adsorbent's structure was confirmed by CHNP, BET, SEM, TGA, XRD, XPS, and FTIR analyses. Batch adsorption studies from synthetic solutions revealed an optimal pH range of 3.0–6.0, where the saturation adsorption capacity reached 0.828 mmol g−1. The adsorption process exhibited fast kinetics (180 min) and was endothermic. Experimental data fitted well with the Langmuir and pseudo-second-order (PSO) kinetic models. The adsorption process was quantitatively described using a new three-dimensional (3D) nonlinear mathematical model, which was verified using MATLAB software against several theoretical models (generalized Langmuir, PSO with Arrhenius, shrinking core, and Floatotherm models). Thermodynamic analysis indicated a spontaneous (ΔG < 0) and endothermic (ΔH > 0) reaction. The adsorbent demonstrated excellent reusability, maintaining high efficiency over six cycles. Metal desorption was successfully achieved using NaHCO3, with adsorption capacity remaining at 88–90% of the initial value after the sixth cycle. Finally, PPA-PGMA was applied to recover U(vi) from acidic ore leachates (El-Sella and Gattar areas) following precipitation pre-treatment. The adsorbent exhibited marked selectivity for U(vi) over co-existing Fe and Si, achieving adsorption capacities of 0.71 mmol U per g (El-Sella) and 0.65 mmol U per g (Gattar). These results confirm the potential of PPA-PGMA as a durable and selective adsorbent for uranium recovery from complex acidic matrices.

This study investigates the recovery of uranium(vi) using a novel functionalized polyglycidyl methacrylate (PGMA) adsorbent, PPA-PGMA, modified with polyamine-phosphonic acid.