Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10239098 | Applied Catalysis A: General | 2005 | 9 Pages |
Abstract
The ammonium salt of 12-molybdophosphoric acid (AMPA) on iron phosphate was synthesized via in situ interaction between the phosphate species of the support and the molybdenum component of ammonium heptamolybdate. The concentration of AMPA was varied such that the nominal MoO3 content of the catalysts was in the range of 5-20Â wt.%. The formation of AMPA, possessing the typical Keggin structure, was confirmed by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) and FT-Raman spectroscopy. Thermo-gravimetric and differential thermal (TG/DT) analyses were used to establish the stability of these catalysts. Whereas the support, FePO4, displayed low activity but maximum selectivity to 2-cyanopyrazine (CP), the in situ synthesized catalysts exhibited higher activity during the ammoxidation of 2-methylpyrazine (MP). At lower reaction temperatures and particularly, at lower AMPA loading, the in situ synthesized catalysts have shown higher activity and retained substantially high selectivity.
Related Topics
Physical Sciences and Engineering
Chemical Engineering
Catalysis
Authors
Ch. Srilakshmi, N. Lingaiah, I. Suryanarayana, P.S. Sai Prasad, K. Ramesh, B.G. Anderson, J.W. Niemantsverdriet,