Influence of lubricants on particulate matter emission from internal combustion engines: A review

Particles endanger the ecosystem and human health in a significant way. Currently, under strict emission regulations, optimizing fuel and combustion systems is no longer enough. Because lubricant consumption is another important factor besides fuel that deteriorates engine PM emissions. A comprehensive understanding of the influence of lubricants on the composition and properties of PM is essential both to reduce PM formation and to optimize PM oxidation. This paper first discusses and summarizes the consumption modes of lubricants and the mechanisms of lubricant-derived particles generation. Then, based on current topical issues, the impact of lubricants on PN emissions is analyzed. Subsequently, the contributions and effects of lubricants on volatile and non-volatile particles are discussed separately. Finally, the effects of lubricant-derived ash on regeneration and catalysis of aftertreatment systems are presented. And suggestions for further research are presented.