Monte Carlo simulation of complex reaction systems : molecular structure and reactivity in modelling heavy oils

Abstract The problem of asphaltene precipitation during their thermolysis in a hypothetical inert oil motivated development of a stochastic model of asphaltene structure, reactions, and product identification. This amounted to stochastic construction of 10,000 asphaltene molecules as a representation of those found in a real resid. The reactions of each molecule, deduced from related model compound reaction pathways and kinetics, provided the reaction of the asphaltene representation after Monte Carlo simulation. A regular solution theory based thermodynamic model assembled the 10,000+ product molecules into global solubility-based product fractions. The simulation data were in good agreement with laboratory data for an off-shore California crude-derived asphaltene.