A multistep procedure for the preparation of palladium-containing zeolite beta spheres using anion-exchange resin beads as shape-directing macrotemplates is presented. In a first step, resin beads are hydrothermally treated with zeolite beta synthesis solutions, and as a result resin-zeolite beta composite particles are obtained. In a second step, anionic palladium precursor species are introduced into the composite using the residual ion-exchange capacity of the resin. Finally, the ion exchanger is removed by calcination, leaving self-bonded palladium-containing zeolite beta spheres. The spheres obtained by the procedure were characterized by AAS, XRD, SEM, EDS, UV-vis DRS spectroscopy, nitrogen adsorption measurements, and chemisorption. Materials with controlled macroshape, porosity, and palladium content were prepared by the method.

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Amorphous titanium hydroxyphosphate with formula Ti(OH)(1.36)(HPO(4))(1.32).2.3H(2)O and a new silica-modified titanium hydroxyphosphate with a general formula Ti(OH)(2x)(HPO(4))(2-x).ySiO(2).nH(2)O are synthesized and characterized using IR, TG, XRD, SEM, solid-state NMR, and BET techniques. It is concluded that SiO(2) is evenly distributed within the titanium phosphate (TiP) agglomerates and that neither the separate silica phase nor the titanium silicates are formed during the synthesis of silica-modified titanium hydroxyphosphate. Correlations between the texture, ion-exchange properties of the amorphous titanium hydroxyphosphate, and the amount of SiO(2) present within the TiP matrix are established. Sorption properties of silica-modified titanium hydroxyphosphate toward Cs(+) and Sr(2+) are studied in a series of samples with an increasing amount of silica, at different pH, and in NaCl solutions with a varying ionic strength. It is found that sorption of Cs(+) does not depend practically on the amount of SiO(2) present, whereas the Sr(2+) uptake drastically decreases with an increase of silica amount. The effects of pH and of the electrolyte concentration on the sorption behavior of titanium phosphate are discussed in terms of ionic hydration shell and titanium phosphate structural specificity. The kinetics of sorption processes is also investigated, and the diffusion coefficients for cesium and strontium are obtained.

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