Removal of U(VI) from aqueous solution by Al 0 /Ni 0 bimetallic material

Abstract

The widespread use of nuclear energy has led to a growing concern over environmental pollution resulted from uranium which has prompted global attention on wastewater treatment. Al⁰ and Ni⁰ metals have been used by numerous researchers both domestically and internationally to removal U(VI) from aqueous solution due to their unique chemical properties. In this work, Al⁰/Ni⁰ bimetallic material (Al⁰/Ni⁰-BM) was prepared by synchronous liquid-phase reduction method. Due to the structure of bimetallic material and synergistic effect, it exhibited a higher removal rate compared with single zero valent metal. The uranium removal rate was 98.90%, well-fitting with the pseudo-second-order kinetic model, reduction model and Langmuir isothermal adsorption model. The high removal performance was attributed to the electron transfer mechanism between material and U element and the adsorption effect of corresponding hydroxides. The thermodynamic parameters demonstrated that the adsorption of U(VI) on the Al⁰/Ni⁰-BM was an endothermic and spontaneous process controlled by physical and chemical adsorptions. In conclusion, Al⁰/Ni⁰-BM showed an excellent potential for understanding U(VI) removal from aqueous solution by zero valent bimetallic materials.