Base Oil – Virgin of various  grades of including  SN150, SN300, SN500 are being exported in Flexi-bags.

Base stocks are called by several names: Neutrals (SN100, SN150, 6SN650) Bright Stocks, Grades (SAE 5, 10…; ISO 22, 32..).

The most common names are for group I (SN: Solvent Neutral), for group II (N: Neutrals) and group III grade names refer to the viscosity (4cst, 6cst, 8cst …).

Group Viscosity Index Saturates Sulphur in % Description
I 80-120 < 90% > 0.03% Conventional (Solvents)
II 80-120 = 90% = 0.03% Requires Hydro-processing
III >120 = 90% = 0.03% Requires severe Hydro-processing, PolyAlphaOlefins (PAO)
IV --- All other basestocks not in Group IV - including other synthetics

Note that the base oil group category is followed by the manufacturing method and then a description of the oil characteristics for each category.

There are five specific categories of base oils. These categories define the type of base stock the oil is formulated from. The categories are as follows..

Group I – Solvent Freezing: Group 1 base oils are the least refined of all the groups. They are usually a mix of different hydrocarbon chains with little or no uniformity. While some automotive oils on the market use Group I stocks, they are generally used in less demanding applications (hh).

Group II – Hydro processing and Refining: Group II base oils are common in mineral based motor oils currently available on the market. They have fair to good performance in lubricating properties such as volatility, oxidative stability and flash/fire points. They have only fair performance in areas such as pour point, cold crank viscosity and extreme pressure wear (hh).

Group III– Hydro processing and Refining: Group III base oils are subjected to the highest level of mineral oil refining of the base oil groups. Although they are not chemically engineered, they offer good performance in a wide range of attributes as well as good molecular uniformity and stability. They are commonly mixed with additives and marketed as synthetic or semi-synthetic products. Group III base oils have become more common in America in the last decade.

Group IV -Chemical Reactions: Group IV base oils are chemically engineered synthetic base stocks.
Poly Alpha Olefins (PAO’s) are a common example of a synthetic base stock. Synthetics, when combined with additives, offer excellent performance over a wide range of lubricating properties. They have very stable chemical compositions and highly uniform molecular chains. Group IV base oils are becoming more common in synthetic and synthetic-blend products for automotive and industrial applications

Group V – As Indicated: Group V base oils are used primarily in the creation of oil additives. Esters and polyolesters are both common Group V base oils used in the formulation of oil additives. Group V oils are generally not used as base oils themselves, but add beneficial properties to other base oils (hh).

Note that the additives referred to in the Group V description are not aftermarket type oil additives. The additives referred to are used in the chemical engineering and blending of motor oils and other lubricating oils by the specific oil company that produces the finished product.

Production Flow Chart
• Feedstock is separated into distillates and vacuum gas oils
• Vacuum gas oil is sent through the hydro-cracker for conversion
• To saturate the molecules and remove impurities such as nitrogen, sulfur, oxygen and heavy metals, Hydrogen is introduced.
• Under extreme temperature and pressure in the presence of a catalyst, hydro-cracking converts aromatics molecules into saturated Paraffin.
• This process yields stock with lighter in color since the absence of contaminants.
• Long waxy paraffin molecules are restructured into shorter ones , so-Paraffin that resist gelling and improve low temperature pump-ability.
• Hydrogen is introduced again to clean up the remaining and impurities thus enhancing the oxidation and thermal stability of the final product.


Test Units Methods 150 SN 500 SN
Density @ 15 °C ASTM-D 4052
Colour - Max ASTM-D 1500 1 2
Flash Point COC - Min°C ASTM-D 92 210 227
Flash Point PMCC - Min°C ASTM-D 93 200+ 210+
Furfural Content - Max PPMM- 1414 5 5
Pour Point - Max°C ASTM-D 97 -12 -6
Viscosity @ 40 °C Cst ASTM-D 445 28/31 91/101
Viscosity @ 100 °C Cst ASTM-D 445 - -
Viscosity Index - Min ASTM-D 2270 95 95
Carbon Residue - MaxWT % ASTM-D 189 - 0.1
Sulfer Content - Max WT% ASTM-D 4294 0.6 1
Neutralization No - MaxMG KOH/GM ASTM-D 664 0.05 0.05
Copper Strip Corrosion - Max100 °C/3 Hrs ASTM-D 130 1A 1A
Ash- Max WT % ASTM-D 482 0.01 0.01
Appearence - Visual C&B C&B

Comparison of Virgin and Re-Refined (Recycled) Base Oil

BASE OIL SN500 Virgin Recycled Standard
Viscosity Index 90 100 ASTM D 2270
Flash Point  deg C 230 min 215 ASTM D 92
Pour Ponit deg C -6 -3 ASTM D 97
Kinematic Viscosity  @ 40 deg C CST 100 100 ASTM D445
Kinematic Viscosity  @ 100 deg C CST 11 10.5 ASTM D445
Density at 15 deg C  KG/L 0.885 0.88 ASTM D 4052
Color 2.5 max 4 to 6 ASTM D 1500