FCC coprocessing oil sands heavy gas oil and canola oil. 2. Gasoline hydrocarbon type analysis

Abstract

This study set out to gain a deeper understanding of a fluid catalytic cracking (FCC) coprocessing approach using canola oil mixed with bitumen-derived heavy gas oil (HGO), for the production of partially-renewable gasoline, with respect to its composition and quality. The FCC coprocessing approach may provide an alternative solution to reducing the carbon footprint and to meet government regulatory demands for renewable transportation fuels. In this study, a mixture of 15 v% canola oil in HGO was catalytically cracked with a commercial equilibrium catalyst under typical FCC conditions. Cracking experiments were performed using a bench-scale Advanced Cracking Evaluation (ACE) unit at a fixed weight hourly space velocity of 8 h−1, 490–530 °C, and catalyst/oil ratios of 4–12 g/g. The total liquid product samples were injected via an automatic sampler and a prefractionator (to remove +254 °C) into a gas chromatographic system containing a series of columns, traps, and valves designed to separate each of the hydrocarbon types. The analyzer gives detailed hydrocarbon types of −200 °C gasoline, classified into paraffins, iso-paraffins, olefins, naphthenes, and aromatics by carbon number up to C11 (C10 for aromatics). For a feed cracked at a given temperature, the gasoline aromatics show the highest selectivity in terms of weight percent conversion, followed by saturated iso-paraffins, saturated naphthenes, unsaturated iso-paraffins, unsaturated naphthenes, unsaturated normal paraffins, and saturated normal paraffins. As conversion increases, both aromatics and saturated iso-paraffins increase monotonically at the expense of other components. Hydrocarbon type analysis and octane numbers with variation in feed type, process severity (temperature and catalyst/oil ratio), and conversion are also presented and discussed.