Improved cement barriers applied in nuclear wastes

Immobilisation of Fe floc: Part 1, pre-treatment of floc with slaked lime

“…They concluded that the most appropriate getter in this application was a zeolite and that getter particle size, cement curing temperature and the ratio of water to cement solids (w:s ratio) had little influence on sorption efficiency. Other research has found that by pre-treating the radioactive waste with hexacyanoferrite ions, active caesium and cobalt are bound and leaching of these elements is reduced after encapsulation in cement paste [10]. With regard to the interaction between radioactive elements and the ferric hydroxide floc, Duff et al [11] stated that uranium (VI) is readily sorbed onto amorphous and crystalline ferric oxides and hydroxides such as hematite and goethite (FeOOH) thus preventing uranium transport.…”