LUO Yi, ZHOU Yasong, WEI Qiang, et al. Effect of citric acid and phosphorus on properties and hydrodenitrogenation performance of MoW/Ni/Al2O3 catalysts[J]. CIESC Journal, 2014, (10): 3916-3923. DOI: 10.3969/j.issn.0438-1157.2014.10.023.
LUO Yi, ZHOU Yasong, WEI Qiang, et al. Effect of citric acid and phosphorus on properties and hydrodenitrogenation performance of MoW/Ni/Al2O3 catalysts[J]. CIESC Journal, 2014, (10): 3916-3923. DOI: 10.3969/j.issn.0438-1157.2014.10.023.DOI:
The trimetallic catalysts were prepared by the iso-volume impregnation method using nickel-molybdenum-tungsten as active metals and γ-Al2O3 as support. The properties of the catalysts modified by phosphorus
citric acid and phosphorus in cooperation with citric acid
as well as the catalytic performance of hydrodenitrogenation and denitrogenation selectivity were examined. The catalysts were characterized with NH3-TPD
Py-IR
H2-TPR
XPS and HRTEM. The results indicated that on the surface of the catalyst modified by phosphorus the amount of weak acid was increased. Also phosphorus promoted the sulfidation of active metals and improved the rate of removal of basic nitrogen and non-basic nitrogen. But phosphorus resulted in the increase of the stacked layers and decreased the dispersion of active metals. Citric acid added in the catalysts could lower the sulfuration temperature of the active metallic oxide
and improve the hydrogenation performance of catalysts; but it had no effect on hydrogenolysis activity
and focused on the removal of non-basic nitrogen. Phosphorus in cooperation with citric acid could not only improve the hydrogenolysis activity of catalysts
but also improve the hydrogenation performance of catalysts. As a result the rate of removal of basic nitrogen and non-basic nitrogen of the catalyst modified by phosphorus in cooperation with citric acid for coker gas oil was remarkably promoted