Hydrofinishing - Stabilization

Hydrofinishing follows extraction or dewaxing. The primary goal is to improve appearance (color, color stability, and oxidative stability) and to remove impurities such as the solvent, nitrogen, acids and sulfur to meet the 

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Oxidation Stability of Hydrofinished and Clay-Treated Oils from Western Canadian Crude... 

All streams were hydrofinished to produce stabilized near-water white final base stocks. 

Mitsubishi made low (4.0 cSt at 100°C) and medium (6.83 cSt at 100°C) viscosity group III base oils, also from hydrocracker bottoms.11 The waxy lube cuts were subsequently both solvent extracted and hydrofinished to stabilize them and finally solvent dewaxed according to their schematic in Figure 7.22. 

D) The final step is dewaxing, and undoubtedly that will be performed by hydroisomerization using one of ExxonMobil s MSDW catalysts. In this case, dewaxing will be followed by a stabilization hydrofinishing step, which would likely obviate the need for step C. 

Organic Sulfur s Good Stability Antioxidant Hydrofinishing... 

Finally, a hydrofinishing step is often used to improve color and stability by saturation of trace multiring species and by removing some residual polar hydrocarbons, e.g. those containing nitrogen. Basestocks from typical crudes have VI ranging from 95 to 105, with saturates contents 65 to 85% and sulfur levels usually above 0.1 wt%. 

Lube Hydrotreating. The mild hydrotreating ( hydrofinishing ) of lube oils improves color, odor, and stability by removing olefins, sulfides and mercaptans. Severe hydrotreating also removes aromatics, nitrogen, and refiiactory sulfur compounds. 

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