MODIFIED TITANIUM PHOSPHATES AS CESIUM SELECTIVE ION-EXCHANGERS

Two synthetic methods for the preparation of spherically granulated ti tanium phosphates (TiP), as cesium selective exchangers, have been car ried out. The first method uses the ''ion memory'' effect for the form ation of specific adsorption sites in the matrix of TiP, whereas the s econd method results in the preparation of granular titanium phosphate - ammonium molybdophosphate (TiP-AMP) composites by a gel technique. The efficiency of the new materials has been studied in complex system s. The cesium distribution coefficients for some of the sorbents prepa red are higher than 40,000 mL/g. It was found that, due to high exchan ge capacity, regenerability and high selectivity for cesium, TiP mater ials with ''ion memory'' effect can be used for radiocesium recovery f rom ground and surface waters, whereas granular composite TiP-AMP exch angers are useful for the treatment of cesium containing acid nuclear wastes with a high content of background electrolytes.