A molecular-level-process model for a fluidized catalytic cracking process was developed. The work was aimed at the coarseness of the reaction network used in traditional lumping kinetic models. A feed-component matrix containing 14692 molecules was generated using a structure-oriented-lumping (SOL) method. A total of 95 groups of reaction rules were compiled, and 702943 reactions were involved. The SOL reaction kinetic model was combined with the reactor model to calculate the temperature distribution and feedback on the complex reaction network by taking into account the reaction heats in each reaction. The model was validated by the industrial data and predicted that the gasoline yield was >51% and the olefin content in gasoline was <24% at proper operation temperatures and catalyst/oil ratios. With the aid of the molecular-level model for the maximizing-isoparaffin technology, the product distribution and corresponding product quality can be controlled rationally by manipulating the operation conditions.

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A Mg-rich Mg–Al spinel modified with CuO and CeO2 via a cogelling method was used to remove SO2 from fluid catalytic cracking (FCC) flue gas. It was found that the generation of a MgO–CuO solid solution was prevented in the presence of CeO2. So CuO had a better dispersion on the adsorbent surface and showed a better catalytic oxidation activity. At the same time, when CuO was added, oxygen defects were found increased greatly in the lattice of CeO2 by Raman spectra and in situ FTIR spectra analyses. This improved the oxygen adsorption capacity of the catalyst. High catalytic oxidation activity and oxygen adsorption capacity of the catalyst enormously promote oxidation of SO2 to SO3, which is much easier to adsorbed by spinel. The SO2 breakthrough time was doubled when the Mg–Al spinel was modified with both CuO and CeO2.