Base Oil is the name given to lubrication grade oils initially produced from refining crude oil (mineral base oil) or through chemical synthesis (synthetic base oil). The base oil is typically defined as oil with a boiling point range between 550 and 1050 F, consisting of hydrocarbons with 18 to 40 carbon atoms. This oil can be either paraffinic or naphthenic in nature depending on the chemical structure of the molecules.
Base oil has two different kinds: Virgin & Recycled
Base oils are refined base stocks recommended for use in the manufacture of automotive & industrial lubricants, oil & greases, rubber products, white & paraffin oil, and so on. Iranian Base oils are refined from crudes with characteristics making them the most desirable for our customers. Base oils are more polar in nature than Paraffinic oils and hence they have good cooling properties and excellent low-temperature properties. They also have better solubility and ability to form stable emulsions. This oil has no impurities or compounds that can have an adverse effect on the quality of the oil. We offer base oils in various viscosity ranges including SN 150, SN 180, SN 350 and SN 500.
Base Stocks, obtained after the above-listed operations are called Solvent Neutral Base Oil (SN) which are distinguished with numbers according to their approximate SUS viscosity at 40°c such as SN150, SN180, SN350, SN500, etc.
In summary, lubricant base oils are categorized by their physical characteristics and/or refining process, as follows:
Group I oils are solvent-refined, which is a simpler refining process, making them the least refined and therefore also the cheapest base oils available. Solvent-refined oils consist commonly of a mix of different hydrocarbon molecules which cannot be distinguished in the refining process. This results in an oil with irregular molecules causing increased friction within the oil. Group I oils are therefore used most often in less demanding applications.
Group II base oils undergo hydrocracking which is a more complicated process than the process for Group I oils. Hydrocracking is a process that breaks down large hydrocarbon molecules into smaller ones. The hydrocarbon molecules of these oils are saturated, giving them better ant oxidation properties. Group II oils are priced closely to Group I oils.
Group III oils undergo an even longer process than Group II oils. The process, called severe hydrocracking, is also more intense. More pressure and heat is applied during the refinery process. This results in purer base oil with a higher quality. Even though Group III oils are derived from crude oil, they are sometimes described as synthesized hydrocarbons.
Group IV base oils are Polyalphaolefins. These are not extracted but made from small uniform molecules. This is also the biggest advantage of PAOs because they can be completely tailored to have a structure with predictable properties. They are very suitable for use in extreme cold or extreme hot conditions.
Group V oils consist of any type of base oil other than mentioned in the previously defined groups. If it is synthetic oil and it is not PAO it is group V base oil. They include, among others, of naphthenic oils and esters. Usually Group V oils are not used as a Base Oil but as an additive to other base oils.
Different Types of Base Oil:
Paraffinic Base Oils (Often referred to as Group I or II): Base Stocks produced using solvent refined & advanced hydrocracking processes. Some of the further developed oils also involve a catalytic de-waxing process to produce a more pure product. The aromatic content of these oils varies by the refining process used. RAHA Oil supplies a variety of highly refined oils that are ideal for a variety of process applications.
Naphthenic Base Oils: Refined from sweet crude oil distillates. Naphthenic base oils have a very low aromatic content and low paraffin (Wax) content. These characteristics allow for a low pour point on lighter viscosities and a high degree of solvency where heavier viscosities are required.
Synthetic Base Oils (Often referred to as Group III, IV &V): Base Stocks that involve a chemically modified base which can be of a petroleum or chemical origin. Group III – Base Oils that have been converted by means of a catalytic process in the presence of Hydrogen, usually under greater pressures. These resulting Base Oils are very pure and refined with superior performance to Group I and II Base Stocks. PAO (Polyalphaolefin) (Group IV) – *for more information, please see our “PAO” page. Synthetic Esters (Group V) – Derived from diesters, polyesters, alkylated naphthalene, alkylated benzenes, etc.) Bio-Based Oils (Group V / unclassified) – Derived from renewable resources that are readily biodegradable. Some of these renewable sources include Sugar, Algae Succinct Acid.
Virgin oil is the most common type of oil used in lubrication products today and sets the standard for oil quality. Virgin oil is a crude oil that’s gone through the refining process but hasn’t been used yet. Once you use it in your machines, it’s downgraded to used oil.
When it comes to recycling your oil, this refers to taking used oil and running it through a filtration system to remove any insoluble impurities. This won’t remove any chemical contaminants, but removing the physical ones can make it suitable to be burned as fuel or re-used in non-critical systems.
Reconditioned oil is a subcategory of recycled oil, where recycled oil is mixed with additives to help prolong its usable life. Reconditioned oil is typically only good for one-time use, however, and not suitable in automobiles.
Uses of Base Oil