Abstract: The properties and hydrocarbon compositions of 9 kinds of hydrotreated lube base oils were analyzed and their structure parameters were calculated by n-d-m method. The relationships between the structure and the hydrocarbon composition of hydrotreated base oil with density, refractive index, average molecular weight were explored. At the same time, the correlation of the alkane, cyclanes content in lube base oil with viscosity index and oxidation stability was tested. The results show that the density of the base oil has a positive correlation with the RT and RA; the refractive index has an approximate positive correlation with the structure parameters (CA, CN) and a negative correlation with CP; the average molecular weight has a positive correlation with aromatic and alkane content, and a negative correlation with the paraffinicity. The paraffin content has a positive correlation with the oxidation stability and viscosity index, but has a negative correlation with the naphthene content.

Key words: hydrotreated lube base oil, density, refractive index, structure, hydrocarbon composition, average molecular weight, viscosity index, oxidation stability