Simulation and Experimental Study on the Effect of Dispersants on Soot Aggregation

Diesel engine technology innovation causes excessive soot accumulated in engine oil.Due to its detrimental effect on lubricant and diesel engine,improving the dispersibility of engine oil to restrain soot aggregation efficiently is the key technique for formulations.In this study,the aggregation of soot and interaction between dispersant and soot were investigated by molecular dynamic simulation.It was found that the molecular interaction between the dispersant and the soot aggregation system had a significant influence on disrupting the soot aggregation.Bis-PIBSI was more beneficial to having more interaction sites with soot molecules,while the mono-PIBSI with a high proportion of polar groups had stronger interaction with soot molecules.According to the simulation result,suggestions for use of additives were proposed.Carbon black dispersancy test was exploited to verify the dispersion effect of different dispersants on carbon black.The results indicate that mono-PIBSI and bis-PIBSI added at suitable mixture ratio to lubricant could perform good dispersion ability.