Hydrotreating is a relatively new process to manufacture high quality lube stocks through ring opening, isomerization, cracking, hydrogen transfer and other hydrogen reactions. Among the advantages of this process over solvent refining are greater crude flexibility, potentially high VI base stocks and increased flexibility in viscosity distribution. The hydrotreated base stocks are manufactured to be equivalent to solvent refined stocks and possess the added benefits of higher VI's, higher flash points and lighter colors. In addition, hydrotreated stocks show improved oxidation inhibitor response. This response is seen in engine oils and industrial lubes. In all other respects, hydrotreated stock performance with current additive systems is equivalent to solvent refined stocks in engine oils, automatic transmission fluids and gear oils.
