Reagents used in chemical separation processes for used nuclear fuel are susceptible to radiolysis. Here we investigate the 10 B(n,α) 7 Li reaction for inducing high linear energy transfer (LET) radiolysis. A solution of tributyl phosphate (TBP) in n-dodecane, representing the PUREX solvent, was irradiated by gamma rays from a 137 Cs source and by high LET particles from the 10 B(n,α) 7 Li reaction in the UC Irvine TRIGA reactor. TBP degradation and Dibutyl phosphate (DBP) formation were quantified by gas chromatography. Our data show a significantly larger formation of DBP in the presence of gamma radiation compared to high LET radiation.