effect of initial temperature on the efficiency of asphaltene adsorption onto lime nanoparticles: a molecular dynamics study

For its main purpose, this work used molecular dynamics simulations to study the adsorption behavior of asphaltene molecules on lime nanoparticles in a water medium at different initial temperatures. the major objective of this research was to find out the role of temperature on the efficiency, strength, and mechanism of asphaltene adsorption onto lime nanoparticles, which are naturally good candidates for the mitigation of asphaltene precipitation in upstream and midstream systems of the petroleum industry. atomic models incorporated asphaltene molecules and 20 wt% lime nanoparticles and allowed to equilibrate for 10 ns to bring the system close to thermodynamic stability with an average temperature of 299.44 k and kinetic energy of 0.86 kcal/mol. further adsorption simulations for an additional 10 ns produced very good results, where asphaltenes were found to saturate, reaching a maximum atomic density of 180.72 atoms/å³ close to the surfaces of the nanoparticles, and an interaction energy of 0.047 kcal/mol, showing that they had formed a very stable adsorption configuration. as much as 69% of the asphaltene molecules would have already stuck to nanoparticle surfaces during the first 7 ns before they approached saturation. the maximum atomic density reduced from 300 k to 350 k to reach a value of 161.37 atoms/å³, the interaction energy decreased to 0.031 kcal/mol, and the adsorption ratio decreased from 69% to 56%, evidence of a temperature-dependent reduction in adsorption efficiency. these findings will shed light on the molecular-level thermal sensitivity aspects of asphaltene strategies based on lime-nanoparticle control. in addition, they will support the development of more efficient nanofluid formulations for petroleum-related applications.