Conversion of residual feedstocks in FCC. Evaluation of feedstock reactivity and product distributions in the laboratory

A method was developed to evaluate the conversion and product distribution of a resid that could be added to conventional VGO feedstocks for FCC processing. An atmospheric tower resid was dissolved into toluene and methylnaphthalene at 15% and 25%, respectively, and converted at 550 degrees C over an equilibrium conventional FCC catalyst in a CREC Riser Simulator laboratory reactor. Reaction times were from 5 to 25 s. The pure solvents were also converted under the same conditions to provide background information. The method was based on the careful assessment of the masses of the reaction products. Results showed that, considering that an interaction is developed between resid and solvent in relation to the catalyst surface, it is possible to evaluate the specific contribution of the resid to the product slate in terms of hydrocarbon groups or compounds of particular interest. In this way, different catalysts could be compared for their performance with different resids and VGOs, or the impact of various factors on the FCC operation could be predicted as a function of resid-related changes.