SYNTHESIS OF NEW ALUMINOPHOSPHATE MATERIALS WITH THE FAU AND AFR STRUCTURE-TYPES

The modification of the synthesis procedure used for the crystallizati on of SAPO-37 (FAU-type), namely an addition of a source of a divalent element Me like Zn or Co in place of, or in addition to silica, a sma ll decrease in the pH and a decrease in the crystallization temperatur e, allowed new MeAPO- and MeAPSO-FAU materials to be obtained. Moreove r, a higher water content of the gel allowed the tetramethylammonium c ation content to be increased and therefore to be closer to the stoich iometric amount. Further, in spite of the presence of tetrapropyl- and tetramethylammonium cations which are specific templates for the FAU- type structure, the synthesis conditions could also be adapted to obta in, but with more difficulty, the new MeAPO- and MeAPSO-AFR-type mater ials. It should be noted that in the absence of Me elements the AlPO4- AFR-type phase formed very easily which is not the case for the AlPO4- FAU-type phase. (C) 1997 Elsevier Science B.V.