PREPARATION AND SOME PROPERTIES OF ZR PHOSPHATE HYPOPHOSPHITE AND ZR PHOSPHATE DIMETHYLPHOSPHINATE WITH GAMMA-LAYERED STRUCTURE

It was found that the interlayer dihydrogen phosphate of gamma-Zr phosphate, other than by O2P(OH)R groups, can be totally or partially replaced by O2PR2 groups (R = H or organic radical). The preparations of two new compounds having composition ZrPO4.O2PH2 (interlayer distance = 8.84 angstrom) and ZrPO4.[O2P(OH)2]0.33[O2P(CH3)2]0.67 (int. dist. = 10.33 angstrom) are reported and discussed. The compounds were characterized by X-ray powder diffraction and thermogravimetric analysis, as well as, after dissolution, by chemical and NMR analysis. The formulation of the gamma-layered compounds can be now generalized as ZrPO4(O2PR'R")1-x(O2PR'"R"")x.nS, where the various R can be H, OH or an organic radical while S is a solvent in the interlayer region. Some considerations on their structure and their ion-exchange properties are also reported.