Incorporation of Mn, Co and Zn cations into large-pore aluminophosphate molecular sieves MeAPO-50

Large-pore metal modified aluminophosphate molecular sieves MeAPO-50 (Me=Co , Zn, Mn) were synthesised by hydrothermal crystallisation using di-n-propy lamine as structure directing agent. EXAFS and XRD analysis show that cobal t(II), manganese(II) and zinc(II) are incorporated into the nonphosphorus t etrahedral framework sites of MeAPO-50 on the threefold-axis site, and on a site in a general position in the unit cell. Results of both methods on di stribution of the metal over the two sites are compared.