Mesoporous H-AlMCM-41 supported NiO-MoO3 catalysts for hydrodenitrogenation of o-toluidine: I. Effect of MoO3 loading

The mesoporous molecular sieve, H-AlMCM-41 (Si/Al = 100) was synthesized hydrothermally and used as support for the preparation of series of sequentially impregnated NiO-MoO3 catalysts. Various amounts of MoO3 (12, 18, 24 and 30 wt.%) along with of 7 wt.% of NiO were loaded in order to optimize the MoO3 loading level for obtaining maximum HDN activity. These catalysts were well-characterized by physico-chemical techniques, such as X-ray diffraction (XRD), N2 adsorption–desorption, SEM, FT-Raman spectroscopy, UV–vis DRS and FT-IR spectra of CO adsorption and tested for hydrodenitrogenation (HDN) of o-toluidine. The change in dispersion with MoO3 loading was studied by FT-IR spectra of CO adsorbed samples. HDN activities of various NiO-MoO3 catalysts were evaluated and the activities are accounted in terms of physico-chemical characteristics of the catalytic materials. Catalyst with 7 wt.% NiO-24 wt.% MoO3 showed maximum HDN activity when compared to other catalysts and its enhanced activity due to the fine dispersion of MoO3 as well as due to formation of an additional Ni–Mo–O phase from AlMCM-41, as revealed by FT-IR of CO adsorption, FT-Raman and XRD studies.