SYNTHESIS OF MNAPO-20, COAPO-20, NIAPO-20, AND CUAPO-20 USING TETRAHEDRAL TETRAHALOMETALLATES

Highly crystalline MnAPO-20 and CoAPO-20 have been prepared at previously unreported substitution levels using tetrahedral tetraharometallates. X-ray diffraction and infrared spectroscopy indicate that framework substitution of manganese and cobalt has taken place. Samples have also been studied using X-ray fluorescence, scanning electron microscopy, thermogravimetric analysis, and a Gouy balance. MnAPO-20 and CoAPO-20 synthesized with metal(II) acetates using the same molar ratios were not as pure as those synthesized using the tetrahedral complexes even at tow substitution levels. Interplanar spacings and unit cell sizes were found to be smaller in these traditionally prepared AlPO4-20 analogs, indicating less framework incorporation of the transition metal. NiAPO-20 and CuAPO-20 have also been prepared by this method, although framework substitution of Ni(II) and Cu(II) is not confirmed.