SMALL PORE ALUMINUM PHOSPHATE MOLECULAR-SIEVES WITH CHABAZITE STRUCTURE - INCORPORATION OF MANGANESE IN THE STRUCTURES -34 AND -44

MnAPO and MnSAPO (APO = aluminum phosphate; SAPO = silicoaluminophosph ate) with -34 and -44 framework structures have been synthesized. Rapi d synthesis of MnAPO-34 could be achieved using morpholine as the temp late that subsequently changes to MnAPO-20 during synthesis. The prese nce of manganese in the framework has been established by a number of experimental techniques. ESR spectra of the low manganese containing s amples were better resolved, and by comparison of these with the ESR o f Mn2+-exchanged samples, it was possible to conclude that Mn2+ was pr esent in the framework of the MnSAPOs. The nature of the silicon site depended on the manganese content of the sample as seen from Si-29 MAS NMR. With higher manganese content, more silica-rich regions next to S APO domains in the framework were formed. In MnAPO-44, a complete orde ring of the T atoms appeared to have been achieved with every P atom b eing surrounded by three Al and one Mn. DTA-TG, infrared, and UV-visib le spectra of the samples will be discussed.