Seeking information on the current status of low-sulfur diesel lubricants in the Chinese market?

In the late 1980s and early 1990s, to prevent environmental pollution caused by toxic substances in diesel engine exhaust, the West **mandated** a reduction in the sulfur and aromatic content in diesel, leading to the development of so-called \"new formula diesel\". Half of these diesel fuels have a sulfur content of less than 0.05%, and their total aromatic hydrocarbon content is less than 35%. In 1991, Sweden introduced two types of environmentally friendly diesel fuels; one of these types had a sulfur content of less than 0.001% and a total aromatic hydrocarbon content of less than 5%. In December 2000, the U.S. Environmental Protection Agency issued regulations on low sulfur content in diesel fuel, requiring that by September 2006, the sulfur content in 80% of diesel fuel used in the United States be reduced from the current level of 500 ppm to below 15 ppm, with full compliance with this standard to be achieved by 2010. California, United States, has stricter limits on diesel content, requiring that the sulfur content in all diesel in the state be reduced to below 15 ppm by 2006. While Europe requires that the sulfur content in diesel decrease from 350 ppm in 2000 to 50 ppm by 2005, it will also introduce \"zero-sulfur\" diesel with a sulfur content of less than 10 ppm starting on January 1, 2005. Immediately afterward, widespread fuel pump failures occurred in Sweden, parts of the United States, and Canada – regions where the sulfur content in diesel **has decreased**. First, adhesive wear of the pump occurs, after which its performance declines rapidly to an unusable level. These failure incidents have drawn attention to the lubricity of fuels. SAE, ISO, and CEC have formed a joint organization to address this issue, and over the past decade, significant work has been done on the lubrication of low-sulfur diesel. Foreign oil companies mainly use lubricity additives to address the lubrication issues of low-sulfur diesel. China’s diesel standards specify that the sulfur content should not exceed 0.2% for premium-grade diesel, and 0.5% for first-grade diesel. Beijing requires that new vehicles meet the European II standard for motor vehicle exhaust emissions (with a sulfur content of no more than 300 ppm); therefore, new vehicles that do not meet this European II standard are prohibited from being sold in Beijing as of January 1, 2003. It is evident that reducing the sulfur content in diesel is an inevitable trend in the development of diesel both domestically and internationally. Acid-type lubricant additives: In the 1990s, J. Lin and others developed an acid-type lubricant additive to reduce the wear rate of the injection systems in low-sulfur diesel engines, particularly the injection pumps and injectors used in such engines. The additive is an alkyl or alkoxy aromatic carboxylic acid compound; adding 50–500 μm/g of this additive to diesel can improve its anti-wear properties. This aromatic carboxylic acid additive is, prior to use, first diluted with a diluent soluble in the fuel oil phase before being added to the fuel oil; the diluent can be mineral oil, as well as polar and non-polar solvents. Non-acidic lubricant additives: Foreign oil companies have conducted extensive research on non-acidic lubricant additives. Caprotti from Exxon used esters synthesized from carboxylic acids and alcohols as lubricity additives for low-sulfur diesel, such as monooleate of glycerol and diisodecyl adipate. It was found in practical applications that adding 0.001–1% of diesel low-temperature flow improvers to these synthetic esters could further enhance the lubricity of the diesel. Dilworth and others improved Caprotti’s technique by using a mixture as an additive: esters synthesized from unsaturated monocarboxylic acids and polyhydroxy alcohols, and esters synthesized from polyhydroxy alcohols with at least 3 hydroxyl groups and monocarboxylic unsaturated acids. These two types of esters are mixed in a ratio of 1:4 to 4:1, and the addition amount is 10–500 μm/g; this approach can significantly enhance the anti-wear properties of low-sulfur diesel. Dilworth et al. improved the anti-wear properties of low-sulfur diesel using ash-free dispersants of nitroacyl compounds in combination with esters synthesized from C2–C50 carboxylic acids and alcohols. Heavy oil type additives

What is the current progress of low-sulfur diesel lubricants? Weren’t the standard requirements set to reduce sulfur content to be implemented soon?

Our team has conducted relevant research in the past; specific details can be found online. As far as I know, diesel with a sulfur content of 50 ppm or less, or even 10 ppm or less, requires the addition of low-sulfur diesel additives. The amount of these additives required varies: abroad it’s several ppm, while in China it’s 10 ppm. The price is around 10,000 to 20,000 yuan per ton (in fact, the effective concentration of these additives is quite low, as they are mostly mixtures with a high proportion of solvents, as well as fats and organic acids). Low-sulfur diesel lubricants can reduce wear on the cylinders caused by the movement of piston in diesel engines, thereby preventing traffic accidents and extending the engine’s operational lifespan. To determine the effectiveness of use, spot-diameter experiments are required; this can be done by the Institute of Rock Mechanics, as well as by Shanghai Petrochemical. However, it is not widely used by domestic refineries; as far as I know, Beijing Yanhua does use it.

From what I understand, the addition amount should range from 80 ppm to 150 ppm; this difference is due to the variations in crude oil used by different refineries, which results in varying requirements for such additions

This post was last edited by qugd on 2011-3-26 at 18:36. Low-sulfur diesel and low-sulfur lubricants are different concepts. Diesel is a type of fuel oil, and new **standards as well as international standards are likely to impose stricter limits on the sulfur content in diesel; as a result, hydroprocessing will become even more important for refineries. It is said that diesel standards in Europe have reached a level where the sulfur content does not exceed 10 ppm in total. There are currently no strict limits on sulfur content in the lubricants and greases used in diesel engines, as certain additives need to be incorporated into these lubricants to provide wear resistance, extreme pressure resistance, and corrosion resistance. These additives may be sulfur-containing, such as certain sulfonates or esters; there are many types of sulfur-containing additives, and at typical addition levels, the sulfur content they introduce is certainly much higher than that in the fuel oil. I think it’s amateurish of the original poster to discuss mixing diesel with lubricants. They really don’t understand the classification and applications of petroleum products at all. It is recommended that the original poster supplement their knowledge on petroleum products.

On July 1, 2011, standards for diesel fuel used in vehicles came into force; diesel with a sulfur content of 350 ppm or less required the addition of diesel lubricants, with a dosage of generally 100–300 ppm being recommended. There are domestic manufacturers, but not many; most of them distribute products of foreign companies or have production facilities established by foreign companies in the country.

Reply to 7# qugd: The lubricant mentioned by the original poster probably refers to the lubricant present in diesel, not machine oil; lubricant should not be considered the same as machine oil. For example: As early as the early 1990s, fuel pump failures became widespread, especially in California and Northern Europe. This phenomenon occurs most often in new cars and vehicles using low-sulfur diesel. The cause of the failure was found to be a lack of lubricity in the fuel. And as far as I know, low-sulfur diesel fuels abroad generally contain lubricants added to improve their lubricating properties. Of course, the proportions used in different regions, as well as the additives employed to improve lubricity, vary. It is known that the United States primarily uses dimeric acids or dimeric esters, while Asia relies mainly on long-chain fatty acids; in Europe, esters are used predominantly (please forgive any possible inaccuracies in this information). In China, diesel meeting National Standard II basically does not require the addition of this substance ； For National Standard 3 gasoline, it might not be necessary to add this substance in some cases ； This must be added to National IV and National V engine oils; otherwise, the lubricity will certainly not meet the required standards.

Reply 1# qichunming1978: National Standard 3 will come into effect after July this year, and it is likely that many refining companies’ diesel will still not meet the requirements. Most lubricant manufacturers obtain pre-formulated imported products and supply them to refineries; the ones truly capable of producing such products are based in Shanghai. They were tested at Takahashi from 2002 to 2004, and it seems that they are now available on the market on an industrial scale.

What was said above is true, but one thing needs to be pointed out: currently, only 60,000 tons of diesel are blended with additives in Shanghai, and the maximum level of these additives is 230 ppm, which is much higher than that in other imported lubricants. Of course, the price will also be much lower, but overall it still doesn’t offer much of an advantage (unless there are other reasons). Moreover, there are likely to be many refineries in the country that will not be able to meet the targets set for July; many of them may have to wait until the end of the year, next year, or even later. . . .