Hydrodenitrogenation activities

Abstract The Zr (Ti)-Si-Al HDN Catalytic Materials have been synthesized rapidly with a new route heated by microwave. The synthesis conditions such as synthesis temperature, microwave oven pressure, pH value of synthesis solution and raw material were examined by experimentation. The thermostability, pore volume, surface area, surface Si/Al and hydrodenitrogen activity of the synthesis samples were also characteristiced. 

A Comparison of the Hydrodesulfurization and Hydrodenitrogenation Activities of Monolith Alumina Impregnated with Cobalt and Molybdenum and a Commercial Catalyst... 

A trickle-bed reactor was used to study catalyst deactivation during hydrotreatment of a mixture of 30 wt% SRC and process solvent. The catalyst was Shell 324, NiMo/Al having monodispersed, medium pore diameters. The catalyst zones of the reactors were separated into five sections, and analyzed for pore sizes and coke content. A parallel fouling model is developed to represent the experimental observations. Both model predictions and experimental results consistently show that 1) the coking reactions are parallel to the main reactions, 2) hydrogenation and hydrodenitrogenation activities can be related to catalyst coke content with both time and space, and 3) the coke severely reduces the pore size and restricts the catalyst efficiency. The model is significant because it incorporates a variable diffusi-vity as a function of coke deposition, both time and space profiles for coke are predicted within pellet and reactor, activity is related to coke content, and the model is supported by experimental data. 

The hydrodenitrogenation activity for both, mono- as well as bidispersed, decreased significantly within 100-150 hr of oil-catalyst contact time. Carbonaceous depositions seem to be the primary cause for catalyst activity decay. 

Figure 2. Catalyst hydrodenitrogenation activity response. Feed FMC oil catalyst BD pressure 1500 psig H2/oil ratio 7500 scf/bbl space time 2.99 hr (LVHST). (O), 371°C (700°F) (U), 427°C (800°F) (A),...

C) Under the reaction conditions of this study there seems to be no difference in the hydrodenitrogenation activity of MD and BD catalysts for hydrotreating raw anthracene oil. 

D.S. Soni and B.L. Crynes, A comparison of the hydrodesulfurization and hydrodenitrogenation activities of monolith alumina impregnated with cobalt and molybdenum and a commercial catalyst, ACS Sympos. Ser. 756 207 (1981). 

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