SYNTHESIS OF NEW MICROPOROUS ALPO4 AND SUBSTITUTED DERIVATIVES WITH THE LTA STRUCTURE

Real AlPO4 and (Si, Me = Co, Zn ...)-substituted derivatives with the LTA structure crystallize from hydrogels containing tetramethylammonium cations, diethanolamine and fluoride anions under carefully controlled preparation conditions including mixing and aging steps. The structure determination from X-ray diffraction (XRD) data, obtained with a single crystal, shows that four different templates are located in four sites of the cages and cavities: F- in the D4R, N(CH3)4+ in the sodalite cage, diethanolamine and water in the eight-ring and near the six-ring of the large alpha cage, respectively. Chemical analysis, thermogravimetry (TG), difference temperature analysis (DTA) and magic-angle spinning nuclear magnetic resonance (MAS NMR) of F-19, P-31, Al-27, Si-29 and C-13 results agree with the structure determination results.