Much palladium forms during the fission process. In nuclear reprocessing, not all of the fission palladium dissolves; also some palladium that dissolves at first comes out of solution later. Palladium-rich dissolver fines (particles) are often removed as they interfere with the solvent extraction process by stabilising the third phase.
The fission palladium can separate during the process in which the PUREX raffinate is combined with glass and heated to form the final high level waste form. The palladium forms an alloy with the fission tellurium. This alloy can separate from the glass.
Pd is the only long-living radioactive isotope among the fission products and its beta decay has a long half life and low energy, this allows industrial use of extracted palladium without isotope separation.
Palladium-109 will most likely have decayed to stable silver-109 by the time reprocessing happens. Before reaching silver-109, a nuclear isomer will be reached; . However, unlike for  there is no current use for .