A strategy for the preparation of super-hydrophilic molybdenum disulfide composites applied to remove uranium from wastewater

Abstract

Due to the radioactivity of uranium, the discharged nuclear wastewater not only causes certain damage to the ecology, but also causes certain harm to human life and health. Adsorption is considered to be one of the most effective ways to remove uranium. In this paper, a kind of MoS₂ adsorbent was prepared by the solid phase synthesis method and functionalized with NiCo-LDH. The raw materials of MoS₂ are cheap and easy to obtain, and the preparation conditions are simple, and large quantities can be obtained without limitations. MoS₂ functionalized with NiCo-LDH provides more adsorption sites for the adsorbent and at the same time improves the hydrophilicity of the adsorbent, so that the active sites can fully combine with uranyl ions. The maximum adsorption capacity of the Langmuir isothermal adsorption model is 492.83 mg g⁻¹. The selective adsorption capacity of uranium can reach 76.12% in the multi-ion coexistence system. By analyzing the adsorption mechanism with FT-IR and XRD, it is believed that on the one hand, UO₂²⁺ forms a covalent bond with Mo in MoS₂ and coordinates with S on the surface of MoS₂. On the other hand, UO₂²⁺ enters the NiCo-LDH layer for ion exchange with NO₃⁻ and coordinates with –OH on the surface of NiCo-LDH. The successful preparation of the MoS₂/NiCo-LDH composite provides a certain application prospect for the uranium adsorption field.