Technical Specifications
| Property | Unit | Typical Value | Test Method |
|---|---|---|---|
| Appearance | — | Brown red liquid | Visual |
| TBN | mgKOH/g | 415 | ASTM D2896 |
| Calcium | % | 15.85 | ASTM D4951 |
| Sulphur | % | 1.45 | ASTM D4294 |
| Flash Point | °C | >190 | ASTM D93 |
| Density at 20°C | kg/m³ | 1220 | ASTM D4052 |
| Viscosity at 100°C | mm²/s | 100 | ASTM D445 |
| Color | — | 2.0 | ASTM D1544 |
| Moisture content | % | 0.08 | ASTM D95 |
| Mechanical impurities | % | 0.03 | ASTM D473 |
* Typical values from batch production. Batch-specific COA available on request.
Technical content reviewed by the CheMost additives team · Specifications last reviewed
Molecular Structure
Supramolecular structure · overbased
Ca₂[R–C₆H₄–SO₃]₂ₓ·(CaCO₃)ᵧ
Colloidal CaCO₃ micelles stabilised by a calcium sulfonate surfactant shell — a higher overbased "y/x" reserve than a conventional detergent, which is what carries C400's TBN 415.
What Is Overbased Calcium Sulfonate (C400)?
CheMost C400 is a synthetic overbased calcium sulfonate detergent, made by sulfonating long-chain linear alkylbenzene and overbasing the resulting calcium sulfonate to a very high reserve alkalinity. It is a metallic detergent — it both cleans and neutralises acid. It carries a TBN of 415 mgKOH/g at 15.85% calcium — among the highest base numbers in the calcium-sulfonate family.
Structurally it is a colloidal dispersion of amorphous calcium carbonate (CaCO₃) packed inside an inverse micelle and stabilised by a calcium alkylbenzenesulfonate surfactant shell. That carbonate core is the acid-neutralisation reserve; the surfactant keeps it oil-soluble and surface-active. The defining feature of C400 is density of reserve: a higher CaCO₃-to-surfactant ratio than a balanced detergent, which lets a formulator reach a target finished-oil TBN at a lower treat rate, or push a higher reserve for severe-duty service.
How C400 Works
Maximum acid-neutralisation reserve
The colloidal CaCO₃ core neutralises the strong acids formed when high-sulphur fuel burns and when the oil oxidises, protecting bearings and cylinder surfaces from corrosive wear. At TBN 415 each unit of treat carries more base than a conventional detergent.
High-temperature detergency
The surfactant shell adsorbs onto deposit precursors and keeps them suspended in the oil, preventing varnish and lacquer from baking onto hot ring-belt and piston surfaces.
Lower treat for the same base reserve
Because TBN is a product-level figure, a higher-TBN grade reaches a given finished-oil base number at a lower treat rate — freeing formulation space for the rest of the additive package, or allowing a higher total reserve where duty demands it.
Rust & corrosion protection
Calcium sulfonate detergents are long valued for their rust-inhibiting surface activity and good water tolerance — useful in marine and wet-duty diesel service.
C400 vs C300 vs M400 — Choosing the Right Grade
All three are CheMost overbased sulfonate detergents in the same family; they differ in base reserve, metal and ash behaviour. C400 is the super-high-base calcium grade.
| Property | C300 | C400 | M400 |
|---|---|---|---|
| Chemistry | High-base calcium sulfonate | Overbased calcium sulfonate | Overbased magnesium sulfonate |
| TBN (mgKOH/g) | 320 | 415 | 420 |
| Metal | 12.5% Ca | 15.85% Ca | 10.0% Mg |
| Sulphur | 1.40% | 1.45% | — |
| Viscosity at 100°C | 45 mm²/s | 100 mm²/s | 110 mm²/s |
| Best for | Balanced detergency + acid control for extended-drain HDDEO and high-sulphur-fuel oils | Maximum base reserve per unit treat — a TBN-booster concentrate for HDDEO, marine and high-sulphur-fuel packages | Lower-ash base reserve for high-grade gasoline and gas-engine oils |
Need a balanced workhorse detergent rather than a booster? See C300. Need the same reserve at lower ash? See M400.
Applications
C400 is used as the overbased calcium detergent / TBN-booster component in formulations targeting the categories below.
Heavy-duty diesel engine oils
Supplies the high reserve alkalinity needed for extended-drain and high-soot diesel service, supporting formulations targeting API CK-4/CJ-4 and ACEA E-category cleanliness and acid control.
Marine & high-sulphur-fuel oils
The biggest demand for very high TBN detergent is in marine and stationary engines burning high-sulphur fuel, where large amounts of sulphuric acid must be neutralised. C400’s TBN 415 makes it efficient as a concentrated base source.
TBN-booster in additive packages
Used to lift the reserve alkalinity of a detergent–inhibitor package without raising treat rate, helping a blender meet a target finished-oil TBN economically and extend oil life.
Industrial gear & circulating oils
Where rust protection and acid control matter, C400 contributes reserve alkalinity plus the surface activity and water tolerance that calcium sulfonates are valued for in industrial gear and circulating systems.
Finished-oil OEM approvals (e.g. API, ACEA and OEM engine-test sequences) are held by the fully formulated oil, not by an individual additive component.
Treat Rate & TBN Contribution
The C400 technical data sheet gives a total treat range of 0.5–10.0 wt% to achieve the desired performance. Because TBN scales with treat, the first-order base contribution of C400 to the finished oil is:
e.g. 4 wt% → ≈ 16.6 mgKOH/g · 8 wt% → ≈ 33.2 mgKOH/g
Indicative starting points by application, derived from that relationship:
| Application | Indicative treat rate |
|---|---|
| Industrial / general detergency | 0.5–2 wt% |
| HDDEO / PCMO (as the detergent / TBN component) | 1–6 wt% |
| Marine & high-TBN systems | up to 10 wt% |
For context, total detergent treatment in engine oils typically runs 6–10 wt% (higher still in marine cylinder oils). Because C400 carries TBN 415, a blender can reach a target base reserve within that envelope at a lower treat than a lower-TBN detergent — which is the point of a super-high-base grade.
Indicative starting points derived from the TBN/treat relationship above, not fixed dosages. C400 is one component of the additive system; the final treat rate must be confirmed against your target performance, ash/spec limit and co-additive package. CheMost can provide formulation and treat-rate support on request.
Formulating With C400 — Complementary Additives
A detergent covers acid control and hot-surface cleanliness; a balanced crankcase package pairs C400 with additives that cover the rest of the performance envelope:
Ashless dispersants
The detergent–dispersant balance is the backbone of every crankcase package: C400 neutralises acids and cleans hot surfaces, while an ashless dispersant suspends low-temperature soot and sludge. The two are complementary, not interchangeable.
ZDDP antiwear additives
ZDDP provides antiwear protection and secondary antioxidancy. Detergent and ZDDP levels are balanced together to manage the total metal/ash and acid-base budget of the oil.
Antioxidants
Phenolic and aminic antioxidants slow the oxidation that generates the acids C400 must neutralise — extending both oil life and the usable base reserve.
Phenate & salicylate co-detergents
Modern packages often blend sulfonate detergents with phenates or salicylates (hybrid surfactant systems) to combine sulfonate rust protection with the high-temperature and antioxidant strengths of the other chemistries.
Documentation, Qualification & Regulatory Support
Standard documentation — Certificate of Analysis (COA, per shipment), Technical Data Sheet (TDS) and Safety Data Sheet (SDS, GHS/CLP) — is provided. The full TDS is available on request rather than as a public download. Additional support is available on request:
Regulatory documentation
REACH, TSCA and country-specific market-registration documentation support available on request.
Third-party inspection
SGS / Intertek / BV pre-shipment inspection can be arranged on request.
Custom grades & packaging
Custom grades and packaging — metal drum, IBC, ISO tank.
Formulation support
Treat-rate calculation and formulation guidance from our technical team.
Packaging & Supply
C400 is stocked and shipped worldwide, with a typical lead time of 1–15 days and a 36-month shelf life at ambient temperature. Samples and quotations are answered within 12 hours.
Packaging
200 kg metal drum · 1000 kg IBC tank · ISO bulk.
Minimum order
1 drum or 1 IBC — no minimum order value.
Incoterms
FOB · CIF · EXW, to suit your freight arrangement.
Loading ports
All major Chinese ports.
Frequently Asked Questions
What is overbased calcium sulfonate (C400)?
It is a synthetic calcium sulfonate detergent overbased to a very high reserve alkalinity — TBN 415 mgKOH/g at 15.85% calcium. Colloidal calcium carbonate is held inside a calcium alkylbenzenesulfonate micelle, giving a concentrated source of acid-neutralising base plus high-temperature detergency for engine and marine oils.
Is C400 the same as calcium sulfonate grease?
No. C400 is a liquid lubricant additive — an overbased calcium sulfonate used as a detergent / TBN booster in finished oils. Calcium sulfonate grease is a separate product in which highly overbased calcium sulfonate is converted into a grease thickener. They share a chemistry family but are different products for different uses.
How does C400 differ from C300?
Both are calcium sulfonate detergents. C300 is a balanced high-base grade (TBN 320) for general detergency and acid control; C400 is overbased to TBN 415 with higher calcium (15.85%), so it delivers more base reserve per unit treat — useful as a TBN-booster concentrate for severe-duty, marine and high-sulphur-fuel formulations.
What treat rate should I use for C400?
The TDS gives a total range of 0.5–10.0 wt%. As a first approximation the finished-oil base contribution is treat % × 415 ÷ 100 (so 4 wt% ≈ 16.6 mgKOH/g). The right level depends on your target TBN, ash limit and the rest of the package; our technical team can assist with the calculation.
How is C400 supplied, and how fast can I get a sample?
C400 is supplied in 200 kg metal drums, 1000 kg IBC tanks and ISO bulk, and shipped worldwide with a 36-month shelf life. As a manufacturer and sourcing partner (Est. 2013), CheMost responds to sample and quotation requests within 12 hours.