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Lubricating oils. Large number of natural lubricating and specialty oils are produced by blending a small number of lubricating oil base stocks and additives.. Important Properties of Lubricating Oils. ViscosityViscosity Index (VI)Pour pointOxidation resistanceFlash pointBoiling temperatureAc
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1. Lubricating Oil Blending Stocks CHE 735
Navid Omidbakhsh
2. Lubricating oils
Large number of natural lubricating and specialty oils are produced by blending a small number of lubricating oil base stocks and additives.
3. Important Properties of Lubricating Oils Viscosity
Viscosity Index (VI)
Pour point
Oxidation resistance
Flash point
Boiling temperature
Acidity (neutralization number)
4. Undesirable Characteristics High pour points
Large viscosity changes with temp. (low VI)
Poor oxygen stability
Poor color
High cloud points
High organic acidity
High carbon and sludge forming tendencies
5. Lube Oil Processing Solvent deasphalting
Reduce carbon- and sludge forming tendencies
Solvent extraction/Selective Hydro cracking
Improve viscosity Index
Solvent Dewaxing
Lower cloud and pour points
Hydro treating/clay treating
Improve color and oxygen stability
6. Propane deasphalting Propane is used as the solvent to extract the lube oil from the asphalt
The feedstock is contacted with 4 to 8 volumes of liquid propane.
The extract phase contains from 15 to 20% by weight of oil with the remainder solvent.
The heavier the feedstock, the higher the ratio of propane is required.
The raffinate phase contains from 30 to 50% propane by volume and is not a true solution, but an emulsion of precipitated asphaltic material in propane.