Base oils are used as the main raw material to produce all kinds of lubricants. Expanding and improving the quality of base oils has increased industrial efficiency. The more the lubricating oils have better physical and chemical properties, the longer the life of the devices and the less money should be spent on the maintenance and repair of the devices. Based on production method, purity, physical and chemical properties, base oils are divided into five main groups defined by the American Petroleum Institute (API). Oils of the first to third groups are the most used in the production of lubricants and engine oils compared to the other two groups. In this article, we are going to talk about the first and third groups.
Base Oil Group 1 Products BWP : Base Oil SN600
The differences between group 1 and group 3 base oils in the production process
Group 1 base oils are the first generation of oils obtained in refineries. The third group of base oils were obtained several years later than the base oils of the first group. The time interval has led to the development of oil refining technologies, and naturally, the quality of base oils of the third group is higher than the first group.
The production process of group 1 base oils
1- Distillation in the distillation tower
After extraction, crude oil is transported through oil transmission lines to refineries and then to distillation towers. In these towers, with the increase in temperature, the type of petroleum composition changes from liquid to gas and obtains an oil cut.
2- Vacuum distillation
The resulting oil cut contains impurities. At this stage, vacuum distillation takes place and the percentage of purity increases.
3- Cleaning with solvent
In this step, the obtained oil fraction is mixed with solvents such as phenol or furfural. This work causes aromatic impurities, resins and asphaltenes to be separated from the oil cut and dissolved in solvents.
4- Hydrogenation
At this stage, the oil reacts with hydrogen to increase oxidation stability and achieve the desired color. This will destroy the compounds that remain in the oil and cause it to oxidize.
5- Final distillation
The oil obtained during the previous steps does not have the necessary viscosity. At this stage, the oil is re-distilled to reach the desired viscosity.
6- Condensate
After the final distillation, the oil fraction is cooled until the condensation process takes place.
The production process of group 3 base oils
1- Selection of crude oil
The base oils of the third group must be of high purity. Examining and selecting crude oil with high quality and purity is the first step in production. The desired crude oil should have high paraffin and less aromatic compounds and sulfur.
2- Primary refining in the distillation tower
In this step, like the first group, the crude oil is heated to separate the oil fraction from which the third group base oil is extracted.
3- Hydrocracking
This step is done with the presence of catalyst and hydrogen. The role of the catalyst is to increase the reaction rate. During the reaction of hydrogen with the presence of a catalyst, large molecules are broken and become smaller molecules that are saturated and can no longer be oxidized by taking oxygen. In addition to the above reaction, aromatic compounds and sulfur are also removed.
4- Secondary purification with hydrogen
This stage is different from the previous stage and in this reaction, nitrogen and chlorine compounds are separated from the oil. This will completely remove impurities and improve the properties of the oil.
5- waxing
To improve the viscosity index and reduce the pour point, the waxes in the oil are removed with the help of solvents or crystallization methods.
6- Final purification
To achieve high purity, the oil is finally refined and the remaining impurities are separated.
Base Oil Group 3 Products BWP : Base oil 6cst
Comparison between two processes
The process of producing and refining oils of the third group is much more complicated and longer than the first group. The number of purification stages and the variety of purification with different elements make the chemical and physical properties of the base oil of the third group better than the first group and it is more resistant to oxidation.
Differences between group 1 and group 3 base oils in chemical and physical properties
The important chemical and physical properties that are investigated in base oils are five, which include viscosity, viscosity index, pour point, oxidation stability and volatility. In the following, we will compare these properties quantitatively and qualitatively and explain what effect each of these factors has on the oil.
1- Viscosity at 100 degrees Celsius
The first group of base oils: between 4.9 and 13 cst
The third group of base oils: between 4.2 and 6.2 cst
Viscosity is the rate at which the substance flows on the surface, which has a direct relationship with concentration. Group 3 base oil is used to produce high quality engine oil and lubricants. Base oils of the first group have limited use. It is possible to use this product in the production of industrial lubricants with low physical and chemical properties.
2- differences between group 1 and group 3 base oils in viscosity index
Viscosity index shows how the viscosity of a material changes due to temperature change.
First group base oil viscosity index: less than 120
The third group base oil viscosity index: more than 120
The higher this number is, it shows that the viscosity of the oil does not change much at different temperatures. If the viscosity index is low, it means that the oil becomes too thin at high temperatures and too thick at low temperatures. This feature is not suitable for oils that work in variable temperature conditions.
3- Oxidation stability
Oxidation stability of a material is considered as the resistance of the material against the reaction with oxygen. In the field of oils, the smaller the chemical compounds of the oils, the lower their tendency to react with oxygen. Oxidation of the oil causes the physical and chemical properties of the oil to harmful changes and no longer have the desired efficiency. As you saw in production section, due to the better purification of the base oil of the third group, especially the hydrocracking process, the antioxidant properties of the third group increased. Finally, it can be said that the base oil of the third group has more oxidation stability than the first group.
4- pour point
Pour Point is the lowest temperature at which an oil or petroleum liquid still has the ability to flow and be fluid. In other words, if the temperature of an oil reaches its pour point, the oil will thicken and will no longer flow easily.
The maximum pour point of the base oil of the first group: -3 degrees Celsius
The maximum pouring point of the base oil of the third group: -18 degrees Celsius
You can see that due to its high purity, the base oil of the third group has the ability to lubricate at a lower temperature.
5- volatility
The volatility of an oil refers to the rate at which the oil changes from liquid to vapor at a certain temperature. In high pressure and temperature working conditions, the oil should not evaporate. In the power transmission cylinders and arms that are driven by the transmission fluid, the oil is under high pressure conditions. In this situation, an oil with less volatility is desirable. The volatility of the base oil of the third group is much lower than the first group.
The volatility of an oil depends on two factors:
Molecular structure
The base oils of the third group have a very regular and uniform molecular structure. The molecules of these oils are mainly composed of long-chain saturated hydrocarbons. This regular structure makes the intermolecular forces stronger and as a result, the oil tends to evaporate less.
Production process
Group 3 base oils are produced using highly advanced refining processes such as hydrocracking and hydroisomerization. These processes remove impurities, aromatic compounds and unsaturated compounds from the oil. This increases the oxidation stability and reduces the volatility of the oil.
Differences between group 1 and group 3 base oils in performance and applications
In the previous two sections, it can be clearly seen that due to the purity and better mechanical and chemical properties of the base oil of the third group, the application of the third group is wider. Of course, the best properties are not considered everywhere, and the focus is mostly on reducing costs. In the following, we describe the applications of the two groups.
Application of third group base oils
Before stating the applications, it is necessary to note that industrial oils and greases are not made up of only one substance and are a combination of several chemical substances. Therefore, when it is said that it is used in certain situations, it means that the main composition To make the oil required for that position is the base oil of the third group.
Engine oils
Third group base oils are used in the production of high quality motor oils for passenger cars, heavy vehicles and industrial equipment due to their high thermal stability and high viscosity index.
Gear oils
Due to their resistance to pressure and wear, these oils are suitable for use in car gearboxes and industrial equipment.
Hydraulic oils
Base oils of the third group are used in hydraulic systems due to their high oxidation stability and suitable viscosity index.
Turbine oils
These oils are suitable for use in steam and gas turbines due to their high thermal stability and resistance to oxidation.
Compressor oils
Third group base oils are used in air and gas compressors due to their low volatility and high thermal stability.
Industrial lubricating oils
These oils are used in various types of industrial lubricants such as greases, cutting oils and molding oils.
The use of base oils of the first group
Industrial oils
Hydraulic oils: used in hydraulic systems with low pressure and medium temperature.
Gear oils: used in industrial gears with low to medium loads.
Turbine oils: used in turbine systems with low operating temperatures.
General lubricating oils
Lubrication of metal parts in various industries such as textile industries, papermaking, etc.
Lubrication of molds and tools in metal forming processes
Advantages and disadvantages of using first and third group base oil
We will start with the first group:
One of the advantages of using the base oils of the first group is the cheapness of this oil. This oil can be used for the lubrication of machine parts that do light work or their efficiency is not high. In fact, there is no need to spend a lot of money for small work.
The availability of this oil is another advantage of this type of oil. In fact, this type of oil can be found in any mechanic or workshop, and there is no need to order refineries to produce it.
The two disadvantages of using the first group oil, which we did not mention above, are deposits and higher fuel consumption. Impurities in the oil after some time cause mass to close around the oil movement ducts. With the seal of these channels, it is difficult to transfer oil and you cannot expect high lubrication. This very hard lubrication makes machines withstand a lot of pressure and require more energy to move. To produce more energy, more fuel is needed.
Among the advantages of the third group, we can mention the reduction of repair costs and the creation of less wear and friction in parts. Proper lubrication in the components of a gearbox reduces the friction between the gears, this prevents the formation of iron burr. Usually, small iron burr cause system failure, for which you have to pay a lot of money to repair them.
The only disadvantage of third group oil is its relatively high price. Of course, it cannot be called a disadvantage because the price increases as the quality increases. In some cases, the second group of base oils can be used instead of the third group.
Conclusion
In this article, we tried to explain to you all the differences between group 1 and group 3 base oils. We hope that by reading this text, you will have a broader view of the base oils of the first and third groups. You can contact our experts for more advice on choosing the right base oil and information on base oil prices. Blackwater company is one of the successful companies in the production of base oils. Expertise and experience are the first words in our collection. The combination of these two factors improves the quality of the oils produced by our company.
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