A hybrid sponge with guanidine and phytic acid enriched surface for integration of antibiofouling and uranium uptake from seawater

In seawater, biofouling caused by marine organisms’ adhesion on the surface of adsorbent would lead to a significant decrease in adsorption property. Herein, a poly (guanidine-hexamethylenediamine-phytic acid) hybrid sponge (PGHPA-PDF-MF) was synthesized for integration of uranium uptake from seawater with antibiofouling property. The PGHPA-PDF-MF sponge exhibited the superhydrophilicity and retained nearly 29 kPa of compression stress after 1000 cycles. Noteworthy, the PGHPA-PDF-MF sponge showed obviously anti-algae growth behavior (88% cell death rate) due to its guanidine and phytic acid groups, as well as inhibit adhesion of algae (Nitzschia) and mussels (Mytilus edulis) by the co-effect of its function groups, 3D porous sponge structure and superhydrophilic surface. The saturated U-uptake amount of PGHPA-PDF-MF sponge was high as 531.9 mg/g at nearly seawater pH (~8.0). At 5th cycle, the sponge still had superior reusability and maintained a high removal amount (200.7 mg/g). The uranium uptake amount of PGHPA-PDA-MF sponge was 44.75 mg/g with 90.9% of removal efficiency in uranium and Nitzschia contained artificial seawater at 7 days. Furthermore, more than 80% of uranium removal rate for the PGHPA-PDF-MF sponge in natural seawater (Bohai, China) also showed its great potentiality for actual application.