Content on this page requires a newer version of Adobe Flash Player.

Get Adobe Flash player


Petroleum Products

Base oil is an oil made out of crude oil to which additives and other substances are added to produce a lubricant (a typical lubricant contains at least 90% base oil and less than 10% additives). A lubricant is by definition a substance used in various industries and equipments (automotive sector being the prime consumer) to reduce wear and lower friction between moving parts.Each crude oil, which base oils are made from, has specific properties which are passed onto its refined products. These include viscosity, sulphur, color, density, flash point, pour point and volatility which define the quality of the products made from the crude oil.

Base Oils are divided into several groups (I, II, III, IV and V) based on the saturates, sulphur, and Viscosity Index content. For instance, group I Base Oils and Group II Base Oils differ in the fact that Group II has a lower sulphur content and a higher proportion of saturates. This difference in quality brings with it, unsurprisingly, a higher cost.

Group I Base oils are named after the way they are refined and their SUS (Saybolt Universal Seconds, a  standard in viscosity) at 100 oC. So SN 150 is a Solvent Neutral with a SUS of 150. The greater the number of the Base Oil is, the higher the viscosity it has. I-products correspond to Industrial grade and used in industrial applications. BS stands for Bright Stock and is very high viscosity base oil which is often used as an additive to heighten viscosity.

 Viscosity is a very important parameter in lubrication applications. It states what the thickness of a solution is, for example: water is thin and has a low viscosity while honey is thick and has a high viscosity. For lubricants, the ability to lower friction is connected to the viscosity. Too high viscosity has an adverse effect on movement and too low viscosity will cause friction to rise between the machine parts. The ideal viscosity gives enough friction reduction without lowering the movement too much. Because the viscosity of a liquid changes with temperature and moving parts tend to heat up, this change is given by the viscosity index. The higher the viscosity index is, the better the lubricant performs in low and high temperatures.

For each application which uses lubricant, different specifications become more important than others. Some focus on achieving under very cold temperatures, others need to perform on a 24h basis; in any case, a lubricant can be tailor-made in order to achieve the desired performance characteristics for the targeted application in a cost effective manner. Since Base Oils are the main ingredients in lubricants, the selection of your Base Oil is the first step in specifying your lubricant formula.

Base Oils
Lubricants have been around since ancient times. The Petroleum-based Lubricants business started in mid 1800’s. The initial processing was limited to separation by boiling point. Most people know the key driver of the production for lubricants are Base Oils.

Here you will read about the different types of Base Oils, followed by a short overview of the base oil production and finally a few basic terms used in the Base Oil Market.

Mineral Base Oil
Modern mineral base oils are the result of a long and complex distillation and refining processes. The feedstock used is crude oil. This substance is not of uniform quality but consists of several thousands of hydrocarbon compounds in which the elements carbon and hydrogen are present in all molecules and, in part, are bound to other elements.

The hydrocarbons can be divided into three main groups: paraffinic, naphthenic and aromatic.

Paraffinic hydrocarbons can be further divided into two subgroups: normal paraffinic and isoparaffinic. Paraffinic hydrocarbons are the best lubricants. The distillation process in the refinery separates the hydrocarbons contained in the crude into cuts based on the molecule size.

Furthermore, as many unwanted substances as possible are removed in the process, such as sulphur, aromatic hydrocarbons, paraffin wax, etc. In other words the mineral oil production process is physical cleaning and the end product is so-called paraffinic base oil.

Most of the hydrocarbons in the base oil are paraffinic, but it also contains naphthenic and aromatic molecules. When the finished lubricant, such as motor oil, is made of these, several additive compounds are used to improve the base oil properties.

The final outcome can also be so-called naphthenic base oil, where most of the hydrocarbons are naphthenic. Their cold properties are excellent.

EHVI and VHVI base oils
VHVI (Very High Viscosity Index) oil, produced from crude oil using special processes, can be made to have properties close to those of synthetic oils. Raw material of the VHVI base oil is paraffinic hydrocracking fraction which is improved by removing waxes using the solvent extraction method.

The use of these base oils as components of modern motor oils is increasing, due to engine constructions that are more demanding in terms of lower emission properties and the new quality requirements of vehicle manufacturers.

Synthetic Base Oil
The group of synthetic base oils covers many different substances: synthetic hydrocarbons, organic esters, polyalkyline glycols, etc. Common to synthetic base oils is their production by a chemical process.

Synthetic PAO (Polyalphaolefine) hydrocarbons are manufactured in a process that results in isoparaffins, the desired types of hydrocarbon molecules. The raw material used is reprocessed into ethene gas (C2H4).

It is thus possible to produce the best possible lubricating oil, which entirely lacks the unwanted components, through chemical processes. This is the most commonly used synthetic base oil in modern engine lubricants.

Base Oils