U(VI) and Th(IV) recovery using silica beads functionalized with urea- or thiourea-based polymers - Application to ore leachate.

Urea and thiourea have been successfully deposited at the surface of silica beads (through one-pot reaction with formaldehyde) for designing new sorbents for U(VI) and Th(IV) recovery (UR/SiO and TUR/SiO composites, respectively). These materials have been characterized by FTIR, titration, elemental analysis, BET, TGA, SEM-EDX for identification of structural and chemical properties, and interpretation of binding mechanisms. Based on deprotonation of reactive groups (amine, carbonyl, or thiocarbonyl) and metal speciation, the optimum pH was ~4.

Assessing the Radiological Risks Associated with High Natural Radioactivity of Microgranitic Rocks: A Case Study in a Northeastern Desert of Egypt.

This study aimed to evaluate the radiological hazards of uranium (U), thorium (Th), and potassium (K) in microgranitic rocks from the southeastern part of Wadi Baroud, a northeastern desert of Egypt. The activity concentrations of the measured radionuclides were determined by using a gamma-ray spectrometer (NaI-Tl-activated detector). The mean (U), (Th), and (K) concentrations in the studied rocks were found to be 3680.