For the sorption of106Ru vapours, natural clinoptilolite was employed mixed with tuff as well as synthetic molecular sieve of mordenite type. Several sorption characteristics of these materials were determined, such as sorption capacity up to 1% break-through, the distribution of sorbed ruthenium along the packing length, the break-through of106RuO4vapours released during the vitrification of model waste solutions and other characteristics of the sorbents. Further, the dependence was determined of the amount of106RuO4passed into the gaseous phase on vitrification time and on temperature.