The α –olefin prepg preparing PAO technology refers to the polymerization of α-olefin under the action of catalyst to produce polyα-olefin synthetic oil (PAO).
PAO has a high viscosity index and a low pour point, making it an ideal base oil for high grade specialized lubricants. In addition,PAO has good oxidation stability, low volatility, excellent thermal stability, excellent shear stability and good compatibility with mineral oils.
The catalysts commonly used in PAO preparation include alchlor,boron trifluorideor metallocene. In general, the preparation of low viscosity PAO from boron trifluoride has high selectivity, but aluminum trichloride is more suitable for making medium and high viscosity PAO, metallocene is good at preparing high viscosity and ultra-high viscosity.
1，Adaptable raw material
α - alkene produced by ethylene oligomerization ,by paraffin pyrolysis or by fetol synthesis.
2， Physicochemical properties of catalysts
Item | Polymerization catalyst |
Density，g/cm3 | 1.3-1.5 |
Viscosity，mm2/s@40℃ | 12.7 |
Melting point，℃ | 5 |
Specific heat，KJ/（kg•℃） | 1.42 |
Item | Hydrogenation catalyst |
Appearance | Black or gray-black cylindrical particles |
Size ，mm | 5 X 5 |
BET，m2/g | 80~150 |
Bulk density，kg/L | 0.9-1.2 |
Radial compressive strength，N/Cm | ≥100 |
Ni，wt% | ≥40 |
Other modifiers，wt% | ≥1 |
3，Process conditions
Item | Polyreaction | Hydrogenation |
Pressure ，MPag | 0-0.5 | 2.0 |
Temperature ，℃ | 50 | 200-250 |
Response time，h | 3 | - |
SV，h-1 | - | 0.5 |
H₂-oil volume ratio | - | 500：1 |
4，Technical flow diagram
5， Process characteristics
The ionic liquid was used as catalyst, can be reused, no solid waste, less waste water, low cost.