The main components of diesel anti-wear agents
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This post was last edited by 6900682 on 2011-3-8 18:18. What are the main components of diesel anti-wear agents? I’d like to know. Thank you. After reviewing relevant materials, the additional information is as follows for everyone’s reference: Abroad, polar aromatic compounds are used to enhance the anti-wear properties of hydrogenated diesel ； Domestic anti-wear agents enhance the anti-wear properties of hydrogenated diesel by increasing the polarity of molecules through long-carbon-chain carboxylic acids with low branching, ester alcohols, and polymers formed between alcohols
Reply 1# 6900682 Long-chain fatty acids
Long-chain fatty acids are more commonly used and are cheaper, but esters are relatively more expensive. Using esters might exceed the unified procurement price.
Simply put: acids (fatty acids) and esters.
They are mainly divided into two categories: 1. Fatty acid-type diesel anti-wear agents； 2. Fatty acid ester-type diesel anti-wear agents.
Sinopec has currently issued a strict ban on the use of ester-based anti-wear agents, and there are no specific updates indicating that this ban will be lifted yet~~~ CNPC and some local refineries still use ester-based anti-wear agents.
Low-oleic acid is possible; many of my clients are doing it
Some insights regarding ester-type diesel anti-wear agents: The Research Institute of PetroChina, abbreviated as SIRI, requires that the acid value of such agents be less than 2 mgKOH/g; this acid value is generally easy to control. (2) It’s the issue of the freezing point; everyone is discussing how to solve this problem related to the freezing point. Firstly, the freezing point of the raw oleic acid must be below 0 degrees. So the problem arises again: the saturated acid content in the ester-based diesel anti-wear agents produced using oleic acid at 0 degrees is around 5.6%, which does not meet the requirements set by the Chinese Academy of Petroleum Sciences. Therefore, using oleic acid at -8 degrees solves this issue completely. (3) Another issue is emulsification; people discuss this phenomenon but do not mention how to address it. This requires that the HLB value of ester-based diesel anti-wear agents be less than 3. The formula for calculating the HLB value is HLB = 20(1 – S/A), where S represents the saponification value of the product. A represents the acid value of the raw oleic acid. I think this HLB value is a very crucial factor; it’s strange that no one has considered discussing this issue. (4) It is the issue of the addition amount of ester-type diesel anti-wear agents; the addition amount for acidic anti-wear agents is 200–300 micrograms, while that for ester-type diesel anti-wear agents is 60–120 micrograms. I’m confused as to why ester-type diesel anti-wear agents are used. (5) The most critical issue is the wear scar diameter: when 200–300 micrograms of acidic diesel anti-wear additive are used, the wear scar diameter is only barely reduced to 405–415 micrometers; whereas with 80–120 micrograms of ester-type diesel anti-wear additive, the wear scar diameter drops below 400 micrometers, and even below 350 micrometers. In summary, I think it’s a systemic issue. There are already domestic manufacturers that produce high-quality ester-based diesel anti-wear agents, yet these are rejected in favor of expensive imported diesel anti-wear agents, or even acidic diesel anti-wear agents whose cost is several times that of ester-based ones. It’s worth exploring.