Abstract
The objective of this work is to understand the influence of small amount of Mo=O (1, 3 and 5 wt.% MoO3) impregnated on FePO4 and its resultant effect on the acidity was studied for the ammoxidation of 2-methyl pyrazine (2-MP) to 2-cyano pyrazine (2-CP) in the temperature range of 380-420 degrees C. The Mo/FeP catalyst characteristics were evaluated by XRD, HAADF-EDS, TPR and NH3-TPD techniques. Primarily, quartz-type XRD phase was observed for the iron phosphate (FeP). The Mo/FeP exhibits MoO3 and quartz type iron phosphate phase. The interface between Mo particles (20 nm) and FeP was clearly established by HR-TEM in 3Mo/FeP. Furthermore, the average atomic composition revealed by HAADF/EDS for 3Mo/FeP as Fe 30.0%, P 40.0% and Mo 1.6% with Fe/Mo surface XPS ratio 6. The greater 2-CP yield of 68.0% on 3Mo/FeP was attributed to enhanced, moderate acid sites coming from MoO3 and cooperation between Mo and FeP at the interface in terms of oxygen and electron transfer to the reactant (2-MP).