| Abstract
| - MnAPO and MnSAPO (APO = aluminum phosphate; SAPO =silicoaluminophosphate) with −34 and −44framework structures have been synthesized. Rapid synthesis ofMnAPO-34 could be achieved usingmorpholine as the template that subsequently changes to MnAPO-20 duringsynthesis. The presence ofmanganese in the framework has been established by a number ofexperimental techniques. ESR spectra ofthe low manganese-containing samples were better resolved, and bycomparison of these with the ESR ofMn2+-exchanged samples, it was possible to conclude thatMn2+ was present in the framework of theMnSAPOs.The nature of the silicon site depended on the manganese contentof the sample as seen from 29Si MASNMR.With higher manganese content, more silica-rich regions next toSAPO domains in the framework were formed.In MnAPO-44, a complete ordering of the T atoms appeared to havebeen achieved with every P atom beingsurrounded by three Al and one Mn. DTA-TG, infrared, andUV−visible spectra of the samples will bediscussed.
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