Rapid removal and easy separation recovery of Cs+ and Sr2+ by zirconium molybdopyrophosphate-functionalized collagen fibers

The removal and separate recovery of radioactive Cs+ and Sr2+ remains a challenge for the sustainable development of nuclear energy. A novel adsorbent (ZMPP-CFs) was prepared by in-situ synthesis of zirconium molybdopyrophosphate on collagen fibers to co-adsorb and recover Cs+ and Sr2+ from radioactive wastewater with good thermal stability and radiation resistance stability. ZMPP-CFs showed high adsorption capacities of 1.125 mmol g−1 for Cs+ and 0.445 mmol g−1 for Sr2+ in a wide pH range of 4–11. Furthermore, ZMPP-CFs column exhibited excellent simultaneous removal of Cs+ and Sr2+ with efficiency over 95%, followed by their perfect separation through gradient elution. Significantly, after four cycles of adsorption-desorption-regeneration experiments, ZMPP-CFs column still maintained superior removal rates and excellent separation performance, indicating high application potential. This work provides an effective method for the removal and recovery of radionuclides, which not only purifies nuclear wastewater, realizes the separation and recovery of Cs+ and Sr2+ for resource utilization, but also develops the application of renewable biomass of collagen fibers to reduce waste accumulation in various aspects.