Polyamidoxime-loaded biochar sphere with high water permeability for fast and effective recovery of uranium from seawater

Given the plentiful uranium resources within the ocean, seawater uranium recovery holds significant importance for facilitating sustainable nuclear power development. There has been extensive research involving biochar materials for seawater uranium recovery. Existing biochar materials, on the other hand, exist primarily as powders, which are difficult to recover from use. Besides, traditional amidoxime-based adsorbents exhibited low uranium extraction rate, thus greatly hindering their practical application. In this study, a biochar sphere loaded with polyamidoxime (PAO) is prepared by using carbonized mycelium and PAO, designated as PAO-BS, in order to extract the uranium efficiently and quickly. Benefited from the ultrahigh porosity, hydrophilicity and water permeability, PAO-BS shows outstanding the adsorption efficiency of uranium. In comparison to other amidoxime-based adsorbents, the PAO-BS material demonstrates a remarkable extraction capacity of 211.35 mg g-1 in simulated seawater with an initial uranium concentration of 16 ppm, implying the high efficiency of functional group utilization in PAO-BS. Collectively, these results indicate that the rapid and highly effective recovery of uranium from natural seawater using PAO-BS has considerable potential.