Removal of surface radioactive uranium(Ⅵ) by graphene oxide modified κ-carrageenan/konjac glucomannan composite hydrogel

Hydrogel is an effective surface radioactive decontamination technology. However, traditional colloid decontaminants face long curing duration and low decontamination rate issues. A peelable hydrogel coating composed of carrageenan, konjac glucan, and graphene oxide (GO) with excellent film-forming performance and decontamination efficiency was explored in this study. The results showed that the GO was effectively dispersed inside the hydrogel, improving the crosslink density and thermal stability of the hydrogel by forming hydrogen bonds with polysaccharide molecules. The GO can effectively enhance the decontamination performance of the hydrogel. For stainless steel, ceramic, glass, and rubber surfaces, the decontamination rates of the hydrogel for 30 min were 96.95 %, 87.6 %, 96.27 %, and 74.5 %, respectively. Furthermore, the decontamination effect was stable to temperature. For cement surfaces, the hydrogel could reach a maximum decontamination rate of 70.68 % after 24 h. The decontamination efficiency of hydrogel was affected by porosity, surface roughness, and GO addition. Moreover, the characterization results of XPS, FT-IR, and SEM/EDS showed that the decontamination process of the composite hydrogel may involve surface wetting, ion diffusion, electrostatic attraction, and physical entanglement. In conclusion, the as-prepared hydrogel has been demonstrated as a green, cost-effective surface decontaminant, which has great potential in the field of nuclear industry fields and environmental remediation.