Highly acid-stable polyvinyl alcohol/chitosan/phytic acid aerogel for selective separation of uranium from actual wastewater

Conventional adsorption materials encounter difficulties in achieving optimal selectivity in uranium-containing wastewater (UCW) because of the low uranium concentration and the presence of diverse coexisting ions. Aerogel, renowned for its abundance of adsorption sites and remarkable structural flexibility, is widely regarded as an innovative material. Nonetheless, its stability in solution hinders its utility in the separation of uranium during wastewater treatment. To counter this limitation, a polyvinyl alcohol/chitosan/phytic acid aerogel (PCPA) was synthesized by employing several polymerization agents. An exceptional degree of selectivity, speed, and stability was achieved in the separation of low concentration uranium from UCW. The results indicated that polyvinyl alcohol (PVA) proved to be the most effective in generating stable aerogels, even when immersed in 0.1 M HCl or acidic UCW. PCPA displayed the highest efficacy in isolating U(VI) in UCW at a pH of 6.0. The novel aerogel exhibited remarkable resistance to ion interference during adsorption, leading to an impressive 96.3 % efficiency in the separation of U(VI) from actual low-concentration UCW. Even after five desorption, PCAC could still achieve U(VI) separation efficiencies of more than 80 %. The adsorption of U(VI) in this aerogel is characterized by chemisorption. PVA plays a crucial role in the condensation process of the aerogel, resulting in an increase in the presence of easily dissociable -OH groups. This, in turn, effectively improves the selectivity of the aerogel. PCPA has demonstrated successful capability in the efficient recovery of uranium from UCW.