Sorption of Th, Pa, U, Np and Pu on silica gel from HNO3, HCl and HCl−ROH solutions was investigated. Equilibrium studies indicated sorption behaviour to vary greatly with the acid used. In mixtures of HCl with different alcohols, distribution coefficints were found to depend on alcohol percentage as well as on acidity. Results were discussed and conditions for possible separations were indicated.