Al-27 MAS and MQMAS NMR have been used to identify and quantify framework and extra-framework (EFAL) aluminum in Y zeolites stabilized by steaming and EFAL extraction using various leaching agents. It is useful to characterize contributions of different Al sites in USY. The decomposition of MAS and MQMAS was carried out with the use of a homemade software called MASAI. it takes benefits from the simultaneously analysis of a high resolved 2D-MQMAS and a quantitative MAS spectra. It allows a quantitative assignment of the framework and extra-framework aluminum species. Global and framework Si/Al ratios have been calculated by Al-27 NMR and compared with Si/Al ratio found by X-Ray diffraction and X fluorescence.
机构:
Univ Lille Nord France, CNRS, UMR 8181, Unite Catalyse & Chim Solide, F-59652 Villeneuve Dascq, FranceUniv Bayreuth, Bayer Geoinst, D-95440 Bayreuth, Germany