Sok Yui

Hydrogenation of Coker Naphtha with Nimo Catalyst

Abstract Bitumen-derived coker naphtha was hydrotreated over three commercial NiMo catalysts in downflow pilot reactors. The tests were conducted by varying temperatures (140-280°C), reactor pressures P (3, 4 and 5 MPa), LHSV (1 and 2 hr−1) and at a constant H2/oil ratio (600 S m3/m3). The maximum temperature was restricted to 280°C owing to reactor plugging. The hydrodesulfurization (HDS), hydrodenitrogenation (HDN), and hydrogenation reactions of diolefins, olefins and aromatics were fitted with a pseudo first order plug flow kinetic model with power term corrections for LHSV and P. With the exception of the diolefins hydrogenation which approaches complete conversion at 200°C, all other reactions were insignificant at temperatures below 200°C. No detectable difference was observed in the activities of the three catalysts tested.

Catalyst Deactivation, Kinetics, and Product Quality of Mild Hydrocracking of Bitumen-Derived Heavy Gas Oils

Abstract To assess mild hydrocracking as an option to improve the quality of the heavy gas oil (HGO) fraction of Syncrudes synthetic crude oil (known as Syncrude Sweet Blend or SSB), severe hydrotreating tests were performed by using Athabasca oilsands bitumen-derived coker HGO, heavy vacuum gas oil, and a blend of the two in a pilot-scale down-flow reactor over a typical commercial NiMo/Al2O3 hydrotreating catalyst. Kinetics of sulfur and nitrogen removal, 343°C+ conversion, and aromatics hydrogenation were investigated by incorporating the effect of catalyst deactivation. The total liquid products (TLPs) from the pilot tests were distilled into naphtha, light gas oil (LGO), and HGO fractions, and the TLPs and distilled products were characterized. Cetane number (CN) was determined by engine test for selected LGOs and by ignition quality tester for all LGOs. The quality of product HGOs as fluid catalytic cracking (FCC) unit feedstock was evaluated by using correlations (developed based on feed properties including GC-MS data) to predict FCC product yields. The CN of the LGOs and the predicted gasoline yields from HGO products were much better than that produced from the corresponding fractions of current SSB. The CN and FCC gasoline yield were related to the level of 343°C+ conversion (i.e., the higher the conversion, the higher the CN and FCC gasoline yield).

Hydrotreating Characteristics Of Coked And Of Hydrocracked Gas Oils From Alberta Heavy Bituminous Oils With Commercial Ni-Mo Catalysts, And Prediction Of Some Product Properties

Pilot scale hydrotreating experiments have been conducted on three synthetic distillates using three commercial Ni-Mo catalysts. Kinetics of hydrodesulfurization (HDS), hydrodenitrogenation (HDN) and aromatics hydrogenation were studied, and catalyst activities were compared. Based on temperatures needed to attain target product quality while maintaining other operating conditions constant, all the catalysts were found to have essentially the same initial activities. Correlations were developed to predict the yield and some product properties, based on operating conditions used. The results show a good fit in all cases for the catalysts and feeds tested.