Lubricant oil generally consists of two parts: base oil and additives. Base oil is the main component of lubricating oil and 

determines the basic properties of lubricating oil. Additives can make up for and improve the deficiencies in the performance 

of base oil and give it some new properties. They are an important part of lubricating oil.

Base oil

Lubricant oil base oil is mainly divided into three categories: mineral base oil, synthetic base oil and biological base oil. 

Mineral base oil is widely used and used in large quantities (about 95% or more), but some applications must use products 

blended with synthetic base oil and biological oil base oil, which has led to the rapid development of these two base oils.

Mineral base oil is refined from crude oil. The main production processes of lubricating oil base oil are: atmospheric and 

vacuum distillation, solvent deasphalting, solvent refining, solvent dewaxing, kaolin or hydrogenation supplementary refining. 

In 1995, China's current lubricating oil base oil standards were revised, mainly modifying the classification method, and adding 

two special base oil standards for low-condensation and deep refining. The most important thing in the production of mineral

 lubricating oil is to choose the best crude oil.

The chemical composition of mineral base oil includes high boiling point, high molecular weight hydrocarbons and 

non-hydrocarbon mixtures. Its composition is generally alkanes (straight chain, branched chain, multi-branched chain), 

cycloalkanes (monocyclic, bicyclic, multicyclic), aromatics (monocyclic aromatics, polycyclic aromatics), cycloalkyl aromatics,

 and oxygen-containing, nitrogen-containing, sulfur-containing organic compounds and non-hydrocarbon compounds 

such as colloids and asphaltene. Bio-based oil (vegetable oil) is becoming more and more popular. It can be biodegraded 

and quickly reduce environmental pollution. Synthetic lubricants have excellent low-temperature performance, 

good lubrication performance and long service life. They can be used in environments such as high load, high speed, 

high vacuum, high-energy radiation and strong oxidizing media. Since all industrial enterprises in the world today 

are seeking measures to reduce environmental pollution, this "natural" lubricant has this feature. Although the cost of

 vegetable oil is high, the increased cost is enough to offset the environmental management costs brought about by 

the use of other mineral oils and synthetic lubricant oil.

Additives

Additives are the essence of modern advanced lubricants. Correct selection and reasonable addition can improve their 

physical and chemical properties, give new special properties to lubricants, or enhance certain properties they originally 

had to meet higher requirements. According to the quality and performance requirements of lubricants, the key to 

ensuring the quality of lubricants is to carefully select, balance and reasonably mix additives. Commonly used additives 

include: viscosity index improvers, pour point depressants, antioxidants, detergents and dispersants, friction modifiers, 

oiliness agents, extreme pressure additives, anti-foaming agents, metal passivators, emulsifiers, corrosion inhibitors, 

rust inhibitors, demulsifiers, antioxidants and corrosion inhibitors, etc.