Incorporation of transition metal ions in MeAPO/MeAPSo molecular sieves

Journal Article · Thu Feb 24 04:00:00 EST 2000 · Journal of Physical Chemistry B: Materials, Surfaces, Interfaces, amp Biophysical

DOI:https://doi.org/10.1021/jp993818j· OSTI ID:20017536

Prakash, A M; Hartmann, M; Zhu, Z; Kevan, L

The synthetic incorporation of transition metal ions into aluminophosphate and silicoaluminophosphate molecular sieve frameworks is studied by electron spin-echo modulation (ESEM) spectroscopy. Based mainly on bulk chemical composition of the product, it has been suggested that divalent and trivalent metal ions such as Mn(II), Co(II), Cr(III), and Fe(III) substitute for framework aluminum sites. On the basis of {sup 31}P ESEM results, the authors originally suggested a framework phosphorus site for the incorporation of metal ions such as Ni(II) and Cr(III) in NiAPSO-5 molecular sieves. This site was later supported for other metal ions such as Ti(IV), V(IV), and Cu(II). This work has extended such studies to Mn(II) and Fe(III) to better understand the metal substitution sites in AlPO{sub 4} frameworks. Irrespective of the particular metal ion, the {sup 31}P ESEM spectra of MeAPO/MeAPSO molecular sieves can be interpreted best on the basis of metal incorporation at a framework phosphorus site. Strong {sup 27}Al modulations are also observed for these materials, which supports the {sup 31}P ESEM results that incorporated metal ions are located nearer to aluminum than phosphorus.

• Research Organization: Univ. of Houston, TX (US)
• OSTI ID: 20017536
• Journal Information: Journal of Physical Chemistry B: Materials, Surfaces, Interfaces, amp Biophysical, Journal Name: Journal of Physical Chemistry B: Materials, Surfaces, Interfaces, amp Biophysical Journal Issue: 7 Vol. 104; ISSN 1089-5647; ISSN JPCBFK
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
CRYSTAL STRUCTURE
IMPREGNATION
MOLECULAR SIEVES
SYNTHESIS
TRANSITION ELEMENTS