Serine Grafted Silica Coated Nanoscale Zero‐Valent Iron with Enhanced Fenton‐Like Degradation of Mixed Organic Solvents of Tributyl Phosphate and n‐dodecane

As global nuclear energy scales up, the annual output of low-to-medium-level radioactive tributyl phosphate (TBP) and n-dodecane organic solvents from spent fuel processing grows. To address this problem, the serine grafted silica coated nanoscale zero-valent iron (Ser-SiO₂@nZVI) is synthesized and used as a Fenton-like catalyst. Ser-SiO₂@nZVI is analyzed through various characterization techniques. The catalytic oxidation performance of Ser-SiO₂@nZVI in the Fenton-like system is evaluated. The effects of catalyst type, temperature, catalyst dosage, H₂O₂ concentration and H₂SO₄ concentration on the degradation of organic solvents are optimized. Nuclear isotope simulation experiments proved that the presence of nuclides do not affect the degradation efficiency, and more than 90% of the nuclides remained in the reaction vessel. Electron spin resonance (ESR) results indicated that the Ser-SiO₂@nZVI/H₂O₂ system produced more hydroxyl radicals than the nZVI/H₂O₂ system. Density functional theory (DFT) calculations further suggested that the catalytic performance of Ser-SiO₂@nZVI is higher, and the adsorption energy between Ser-SiO₂@nZVI and TBP/n-dodecane is greater, making it more likely to adsorb organic solvents on the catalyst surface. This research provides a theoretical basis for the modification of iron-based materials and their application in the treatment of low-to-medium radioactive organic solvents.