Studies on the selectivity of cetrimide for uranium extraction from wet process phosphoric acid

An effective uranium removal using diversified synthesized cross-linked chitosan bis-aldehyde Schiff base derivatives from aqueous solutions

Three new cross-linked chitosan derivatives were yielded through intensification of chitosan with diverse types of bis-aldehydes. The prepared cross-linked chitosan was characterized by FTIR, 1H NMR, XRD, and TGA techniques. TGA indicated an improvement in thermal stability of the cross-linked chitosan compared with pure chitosan. Batch adsorption experiments showed that the three novel cross-linked chitosan bis-aldehyde derivatives possessed good adsorption capacity against U(VI) in the order of BFPA > BFB > BODB (adsorption capacity of the three adsorbents for U(VI) reaches 142, 124, and 114 mg/g respectively) and the adsorption isotherm and kinetic were well described by the Langmuir and the pseudo-second-order kinetic model, respectively. In addition, the prepared cross-linked chitosan bis-aldehyde derivatives were examined as U(VI) catcher from waste solutions.

Novel cationic surfactants: synthesis, surface, antimicrobial studies and applicability as an extracting agent for interested element from monazite mineral concentrate

Two novel cationic surfactants based on palmitic acid were prepared to extract uranium from its fluids. The chemical structures of the surfactants prepared were confirmed spectroscopically. The surface activity of these surfactants was evaluated by measuring their surface tension. The cationic surfactants prepared were also tested for their biological activity against Gram-positive and Gram-negative bacteria and fungi. Subsequently, an attempt was made to use these surfactants to remove uranium from the hydrous oxide cake produced after the alkaline degradation of monazite mineral concentrate. To achieve this goal, several experiments were conducted to determine the optimal conditions for uranium extraction and stripping. Under these optimal conditions, the experimental capacity fitted the pseudo-second order kinetic model. Under the investigated optimal stripping factors of 1 M NaCl, acidified with 0.2 M conc. H2SO4, an A:O ratio of 1:1 and a contact time of 15 min, an uranium stripping efficiency of 83% was obtained for the case study. After the complete stripping process, the marketable uranium concentrate was percipitated using hydrogen peroxide as UO4 H2O with an uranium content of approximately 76%, which was chemically determined and confirmed by EDAX analysis.

Microwave assisted decoration of titanium oxide nanotubes with CuFe2O4 quantum dots for solid phase extraction of uranium

Titanium oxide nanotubes decorated with CuFe₂O₄ quantum dots were prepared and characterized. The prepared nanotubes were used for solid phase extraction of U(vi) in real samples.