Calix[6]arene-Picolinamide Extractants for Radioactive Waste Treatment: Effect of Additional Carboxy Binding Sites in the Pyridine 6-Positions on Complexation, Extraction Efficiency and An/Ln Separation (Eur. J. Org. Chem. 14/2010)

The cover picture shows the complexation of actinide metal ions by picolinamide‐based calix[6]arenes. These ligands possess remarkable efficiency in the extraction of trivalent metal ions even at very high HNO3 concentration and fair selectivity for actinide ions over lanthanide ions, which is useful in the recycling of the spent nuclear fuel. The Partitioning and Transmutation (P&T) strategy would allow the long‐lived minor actinides (Np, Am, Cm) in fast nuclear reactors to be separated and transmutated and would also allow the radiotoxicity in the ultimate waste to be minimized, making nuclear power plants more efficient and sustainable. Details are discussed in the article by M. Mariani, A. Casnati et al. on p. 2675 ff.