The effect of lanthanum and zinc ions on the activity of alumina supported nickel–molybdenum catalysts Original Research Article

Activity studies of a series of nickel–molybdenum catalysts incorporated on alumina modified with lanthanum and zinc ions have been performed. Decomposition of isopropyl and diacetone alcohol as well as ethylbenzene decomposition were used as model reactions. The studies of hydrofining activity of catalysts were conducted on a coal liquid in the conditions of a real process at a hydrogen pressure of 9.0 MPa and at the temperature of 400°C.Support modification with lanthanum and zinc ions affects the catalysts activity in the applied reactions. Zinc ions either do not change or insignificantly increase the acidity of the catalyst surface, whereas incorporation of lanthanum ions decreases it considerably. Modified catalysts revealed a higher yield of acetone, both in the reaction of isopropyl and diacetone alcohol decomposition. A very high yield of acetone was obtained for lanthanum modifications. Dehydrogenation activity was higher for the modified catalysts when compared with the unmodified sample. Modification with the two ions caused a decrease in the hydrofining activity of coal liquid with increasing concentration of the modifier. A markedly bigger drop in the hydrodenitrogenation (HDN) and hydrodesulfurization (HDS) activity was obtained for samples modified with lanthanum.