Highly efficient extraction of uranium(VI) from seawater by polyamidoxime/polyethyleneimine sponge

Extracting uranium from seawater is of great significance for ensuring the sustainable development of nuclear energy. This article designs a simple and mass-produced porous sponge polyamidoxime/polyethyleneimine (PAO/PEI) for uranium extraction from seawater. The prepared porous sponge has excellent flexibility and mechanical strength, which can withstand harsh marine environments. In a 50 mg/L uranyl solution, the maximum adsorption capacity of PAO/PEI is 666.67 mg/g. Moreover, PAO/PEI sponge exhibits excellent selectivity for uranium in competitive adsorption conditions. FTIR and XPS are used to explore the adsorption mechanism, and the results showed that the synergistic effect of amidoxime and amino groups enhanced the binding of uranium(VI). The adsorption capacity after 15 days of enrichment in 100L natural seawater is 9.79 mg/g, and the average rate is 0.653 mg/g/day. The results indicate that PAO/PEI porous sponge has broad application prospects in large-scale seawater uranium(VI) extraction.