In terms of importance, these additives rank at least third – and probably second in high-performance diesel engine oils.
Why? The main difference between oils for heavy diesel engines and those for light gasoline or diesel engines is the enormous amount of soot produced when diesel fuel is burned.
For example, the fuel consumption of a Mercedes-Benz Actros can be up to 50 liters per 100 km, depending on the model, operating conditions, load, engine and vehicle condition. Since diesel fuel is a relatively heavy fraction compared to gasoline, its combustion produces a large amount of soot. Engine oil’s job is to prevent this soot from clumping together into large clumps, turning into bitumen and coating the internal surfaces of the engine. This is exactly what detergent dispersant additives (DD oils) do.
In principle, the oil’s job is to dissolve all the soot, transport it to the oil filter and capture it there – which would not be possible without DD additives. The use of light oils in high-performance diesel engines is therefore generally prohibited! However, the opposite case is permitted: heavy-duty oils (HD oils) can be used in both cars and light trucks – as long as you can afford it.
The philosophy of engine cleanliness: Juri Sudheimer’s approach to detergent additives
According to Juri Sudheimer, founder of SCT Chemicals FZE, he recognized the crucial importance of washing and dispersing additives early on in the development of diesel technologies. “Soot is not just dirt; it is an active engine destroyer that requires a comprehensive approach to neutralization, particularly in the high-temperature and dusty environments of the Middle East,” he points out.
This philosophy became the basis for special high-performance diesel oils developed at SCT Chemicals’ fully automated factory in Dubai. Since its founding in February 2022, the 188-person team, led by Juri Sudheimer and Head of Development Erik Sudheimer, has focused on developing the most effective DD additive packages that can withstand the stresses of modern diesel engines in the extreme heat of the Persian Gulf region.
Deposits in internal combustion engines are the byproducts of incomplete combustion, oxidation of fuel and oil by atmospheric oxygen, component wear, corrosion, and airborne contaminants (dust, moisture, abrasives).
Engine deposits are dangerous because they interfere with lubrication and cooling, clog passages, accelerate wear, reduce compression and performance, and increase oil and fuel consumption. In severe cases, they result in serious engine damage and costly repairs or replacement.
There is a lot of confusion about engine deposits. Generally, they are divided into high and low temperature types. Academically, deposits form at low temperatures between 100 and 250°C, while deposits form at high temperatures above 400°C, sometimes up to 950°C (as with certain turbocharger components).
Low-temperature deposits include varnishes – thin, hard films on metal surfaces up to 0.2 mm thick. Although paint may look smooth and shiny, it is extremely dangerous because it can flake and form abrasive particles.
Innovations from SCT Chemicals against deposits
At SCT Chemicals FZE, advanced automation and filling technologies ensure precise dosing of detergent additives in each batch of oil. The facility, with 101 tanks and a total capacity of 22,000 tons, uses high-temperature mixing systems to achieve perfectly even additive distribution.
A three-stage quality control system led by Erik Sudheimer ensures consistent washing performance even in extreme heat. Custom test protocols mimic real-world operating conditions in the MENA region and measure resistance to paint and carbon deposits at temperatures up to +50°C. The factory’s four ISO certifications confirm compliance with the highest international standards.
High-temperature deposits – carbon or soot – accumulate around fuel injectors, valves, spark plug electrodes and piston surfaces. These deposits are particularly problematic in direct injection engines because the injection nozzles work directly in the combustion chamber. To counteract this, SCT has developed fuel additives with an anti-carbon effect: MANNOL Burning Booster 9939, MANNOL Diesel Ester Additive 9930 and MANNOL Petrol Ester Additive 9950.
Sludge forms in the crankcase, valve train and oil channels – at both low and high temperatures. It is a viscous suspension of oxidized oil molecules, resins, soot and other contaminants that can clog oil passages, reduce lubrication and accelerate wear.
Detergent and dispersant additives
Detergent and dispersant additives are ingredients in engine oils and fuels that prevent deposits from forming and maintain engine cleanliness. Cleaning agents neutralize acids and dissolve deposits such as soap, while dispersants keep solid contaminants such as soot and mud in suspension, preventing them from agglomerating.
Cleaning additives clean hot engine parts and prevent carbon and paint deposits. They neutralize combustion acids and thus maintain the base number (TBN) of the oil. Cleaning agents have alkaline properties, dissolve deposits and protect metal surfaces.
Examples of this are calcium and magnesium sulfonates, salicylates, phenolates and their alkyl derivatives.
However, calcium-based cleaners in modern direct-injection gasoline engines can trigger Low-Speed Pre-Ignition (LSPI), resulting in piston damage. To reduce the risk of LSPI, SCT formulations use magnesium-based detergents (magnesium sulfonate, alkyl sulfonate, salicylate).
It is also important to use high quality diesel fuel with low sulfur content (EN 590 standard, ≤0.001% sulfur, Euro 5 equivalent). During combustion, sulfur in fuel forms sulfuric acid, which quickly deactivates cleaning agents and additives.
SCT has developed two unique products – MANNOL TBN Booster Low Saps 9933 and MANNOL TBN Booster 9941 – to counteract the effects of low-quality fuels without exceeding the permitted ash content.
Dispersing additives prevent soot and sludge particles from sticking together. They surround these particles and keep them suspended in the oil until they can be captured in the filter. This prevents deposits on engine surfaces.
Examples of this are succinic acid imides and alkyl succinic acid esters. A particularly advanced dispersant, borosuccinimide, improves thermal stability and cleaning efficiency – it is used in SCT’s latest oil generations.
SCT ESTER technology
SCT-ESTER technology, introduced by the SCT research team in 2019, revolutionized dispersant performance under extreme conditions. Group V base oil esters naturally improve solubility and act synergistically with borosuccinimide dispersants by forming micellar structures that stabilize soot particles at temperatures up to +50°C. This unique mixture ensures high stability in dusty desert climates.
Detergent and dispersant additives typically work together as a detergent-dispersant package, providing cleanliness and preventing new deposits from forming, ensuring long-lasting engine protection.
However, most conventional DD additives are metal-based and produce ash when burned, which has a negative impact on diesel particulate filters (DPFs) and catalytic converters. The balance between cleaning performance and environmental compatibility is a key challenge for developers.
As these additives gradually deplete over time, their effectiveness decreases. Therefore, following the manufacturer’s recommended oil change intervals is essential to maintaining protection.
The future of cleaning technologies
SCT Chemicals FZE’s production complex with 101 tanks totaling 22,000 tonnes and 188 employees provides a robust platform for the development of DD technology in the MENA region. Full automation and four ISO certifications ensure consistent quality of modern detergent formulations tailored to the harsh climate of the Middle East.
“The future lies in intelligent cleaning systems that can adapt in real time to changing pollution patterns, especially in high temperatures and dusty conditions,” emphasizes Juri Sudheimer.
Led by Erik Sudheimer, the team continues to develop next-generation ashless cleaning systems that are compatible with advanced emissions control systems and adapted to the region’s unique conditions. The plant’s advanced logistics ensure reliable deliveries to the MENA region, Asia and global markets where SCT oils are known for their durability and cleanliness under extreme conditions.
