The hazards of non-standard base oils

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Lubricating oil generally consists of two parts: base oil and additives. Base oil is the main component of lubricants and determines their basic properties. 　　Our country has established corresponding quality standards for lubricant base oils, and these standards are equivalent to those adopted by the global lubricant industry. Only base oils that meet these quality standards can be used to produce various finished lubricants that comply with their respective quality requirements. ?However, at present there is a shortage of base oils in our country as well as worldwide, and the supervision in place regarding quality and environmental protection is insufficient. Driven by profit motives, a large number of so-called \"non-standard\" base oils have emerged in the market in recent years. 　　The so-called “non-standard” base oils, as the name implies, are base oils that do not meet quality standards. “The production process of \"non-standard\" base oils is quite simple; its raw materials come from numerous small oil fields and refineries with rudimentary facilities spread across various locations. Small refineries distill fuels such as gasoline, coal oil, and diesel from crude oil; the remaining heavy fractions then serve as raw materials for custom-base oils. The manufacturer treats these raw materials with concentrated sulfuric acid, causing the heavy aromatics (the dark-colored components) to form an acid sludge with the sulfuric acid and thus be removed. Excess acid is then neutralized with an alkaline solution, resulting in the base oil ready for use (some manufacturers also treat it with a small amount of clay). Throughout this entire process, heavy distillate oil, sulfuric acid, and alkalis are relatively inexpensive; their treatment process is simple, which results in low costs. Moreover, they have a lighter color, making them more attractive in appearance. The supply of these materials is not limited, which is why they are popular among many manufacturers of mid-to-low-grade lubricants. 　　So what are the hazards of using \"non-standard\" base oils? 1. The acid value is very high, typically around 2.0 mgKOH/g, whereas the neutralization value of standard base oils (which is approximately equivalent to the acid value) ranges from 0.02 to 0.05 mgKOH/g. A high acidity level implies strong corrosivity toward equipment, especially when the acidity comes from corrosive sulfuric acid. Equipment that uses non-standard oil often suffers from increased wear, larger gaps within the machine, and higher fuel consumption. Many devices that use non-standard oil also develop pitting on their surfaces, and this is due to the aforementioned reasons. 2. It has a low viscosity index and poor viscosity-temperature properties; its viscosity is very high at low temperatures, resulting in high flow resistance, while at high temperatures it becomes as thin as water, with a very thin oil film that fails to provide the necessary protection. ? 3. High pour point: since there is no dewaxing process during manufacturing, it solidifies at slightly lower temperatures. Its flowability is poor at room temperature in the south during winter, which can lead to blockages in the oil circuits; therefore it cannot be used in winter. ? 4. Poor oxidation resistance, short service life, and the oil color tends to darken easily. 　　Therefore, non-standard base oils cannot be used to produce qualified lubricant products. Although its appearance and color seem light, its quality standards are far below those of standard base oils produced through rigorous processing methods; there is no guarantee of quality when using it, so be sure not to fall victim to unscrupulous manufacturers.