Preaggregation of Asphaltenes in the Presence of Natural Polymers by Molecular Dynamics Simulation
Lucas G. Celia-Silva, Patrícia Costa Oliveira Vilela, Pedro Morgado, Elizabete F. Lucas, Luís F. G. Martins, Eduardo J. M. Filipe
Abstract
Cashew nut shell liquid (CNSL), its extract, cardanol, and polycardanol, are known to influence the dispersion behavior of asphaltenes in model solvent mixtures. CNSL and cardanol act as dispersants, while polycardanol can act as both dispersant or flocculant depending on its molecular architecture, concentration, and asphaltene source. In this work, the preaggregation of asphaltenes in model solvents (toluene, n-heptane, and their mixtures) has been studied by atomistic molecular dynamics simulation. The influence of cardanol, addition polycardanol, and condensation polycardanol as additives has been addressed. The simulation results remarkably reproduce the experimental trends, thus contributing to a better understanding of the molecular processes underlying the stabilization or precipitation of asphaltenes by cardanols and their polymers.