Model based analysis of the effect of 2-ethylphenol addition to n-decane in fluid catalytic cracking over a series of zeolites

摘要

The catalytic cracking of n-decane (C10) purely, representing the conventional gasoil feed, and in admixture with 2-ethylphenol (EP), as a model component for HDO bio-oil, is investigated in a fixed-bed reactor over three faujasites. It was observed that EP induces faster deactivation with time-on-stream (TOS), which was more pronounced when materials with low mesoporous surface area were employed. The gasoline selectivity was also shown to increase more steeply with TOS for an EP containing feed. A 5-lump FCC kinetic model, including selective deactivation functions, was developed and incorporated into a transient reactor model to assess the obtained data and account for the observed effects. With the aid of the model, the above trends were rationalized by an increase in the value of the frequency factors, related to the feed conversion into coke and gasoline. The FCC kinetic model was subsequently integrated into a riser reactor model for pilot level simulations, via the extrapolation of the results obtained based on the transient model for the fixed-bed reactor to the steady-state behavior of a riser reactor. In particular, a unique deactivation factor Phi, reflecting catalyst condition, was introduced in the model for the latter reactor to adequately account for the deactivation functions determined making use of the data acquired in the former. Simulation results demonstrate the significance of the first meters of the riser, as well as the effect of operation parameters, i.e, Phi, EP addition in the feed, inlet catalyst-to-oil ratio, on conversion and selectivities.