| abstract |
The invention provides an industrially advantageous method for producing a crystalline silicotitanate having high adsorption/removal capabilities for cesium and strontium in seawater. The method includes a first step of mixing a silicic acid source, a sodium compound, titanium tetrachloride, and water to prepare a mixed gel and a second step of hydrothermal reaction of the mixed gel prepared in the first step to produce crystalline silicotitanate of formula: Na 4 Ti 4 Si 3 O 16 .nH 2 O (wherein n represents 0 to 8). In the first step, the silicic acid source, sodium compound, and titanium tetrachloride are mixed in such a mixing ratio that the resulting mixed gel may have a Ti to Si molar ratio, Ti/Si, of 1.2 to 1.5 and an Na 2 O to SiO 2 molar ratio, Na 2 O/SiO 2 , of 0.7 to 2.5. |