Preparation of crown ether pillared zirconium phosphonate for Strontium Removal

Finding materials with high adsorption capacity and excellent stability for fission products generated in the nuclear fuel cycle remains highly challenging for nuclear wastewater management and contamination remediation. Herein, acid-resistance crown ether pillared zirconium phosphonate (D-AM-ZrP) was prepared by a directly reacting 4-amino-benzo-18 crown 6 phosphonic acid with zirconium other than the conventional complicated intercalation methods. Remarkably, by proper control of the ratio of phosphoric acid to phosphonic acid, the D-AM-ZrP sample with perfect flower-like and well-ordered interlayer structure was obtained, and exhibited the excellent stability under the irradiation and strong acid conditions, which is due to the strong chemical interaction was formed between the crown ether and α-ZrP. More importantly, this D-AM-ZrP exhibited high adsorption capacity and excellent selectivity for removal of Sr2+ from complicated system including high concentrated HNO3 media and competing ions, and the maximum adsorption capacity for Sr2+ (136.42 mg g−1) was 2 times than pure α-ZrP (63.17 mg g−1) at 0.2 mol L−1HNO3 media, which could mainly be attributed to its excellent stability and specific adsorption sites. These excellent properties of D-AM-ZrP were further confirmed by radioactive experiments, and 95% of 90Sr was removal at 0.2 mol L−1HNO3 media, demonstrating that D-AM-ZrP possessed a promising potential for actual application in nuclear wastewater.