- ▸ Used as a detergent and dispersant additive in engine oils and industrial lubricant packages, where overbased grades neutralize acidic combustion by-products and keep insolubles suspended.
- ▸ Functions as a rust and corrosion inhibitor in rust-preventive oils, metalworking fluids, and protective coatings, forming a tenacious water-displacing film on ferrous surfaces.
- ▸ Serves as the primary thickener and base in calcium sulfonate complex greases, delivering high dropping points, mechanical stability, and inherent water and corrosion resistance.
- ▸ Acts as an oil-soluble surfactant and emulsifier in soluble and semi-synthetic cutting fluids, stabilizing oil-in-water emulsions during machining.
- ▸ Applied as a slushing-oil and temporary-protectant component for steel coil, fasteners, and stored metal parts to prevent flash rust during transit and storage.
A grade-specific Safety Data Sheet (SDS) — with the complete hazard classification, handling precautions, and transport information — is supplied with every shipment and available on request. Confirm all safety and regulatory details against the SDS for your specific grade.
Request SDS →- Calcium sulfonate is the calcium salt of long-chain sulfonic acids — supplied as neutral, overbased (high-TBN), and petroleum-derived grades.
- It is the workhorse for three jobs: a lubricant detergent/dispersant, a rust preventive and corrosion inhibitor, and the thickener in calcium-sulfonate-complex greases.
- Specify by Total Base Number (TBN), form (oil solution vs. semi-solid), and application; the Certificate of Analysis governs.
Calcium sulfonate is one of the most versatile additives in lubricant and rust-prevention chemistry. As a calcium salt of sulfonic acids, it carries acid-neutralizing reserve, disperses contaminants, and lays down a tenacious water-displacing film on steel. RawSource supplies neutral, overbased and petroleum-derived calcium sulfonate grades for lubricant formulation, rust preventives, corrosion inhibitors and calcium-sulfonate-complex greases.
What is calcium sulfonate?
Calcium sulfonate is the calcium salt of organic sulfonic acids. Two feedstocks are common: petroleum (natural) sulfonates, recovered from refining (representative CAS 61789-86-4), and synthetic sulfonates made from alkylbenzene. The product is then made neutral or overbased — overbasing disperses colloidal calcium carbonate into the sulfonate to give a high Total Base Number (TBN) reserve. That TBN reserve is what neutralizes acids in an engine oil and what converts into the gel network of a calcium-sulfonate-complex grease.
Grades and forms
| Grade | Typical TBN | Primary use |
|---|---|---|
| Neutral / low-base calcium sulfonate | ~0–30 | Rust preventives, dispersancy, base for further reaction |
| Overbased calcium sulfonate | ~300–400 | Engine-oil detergent, acid neutralization, grease precursor |
| Calcium petroleum sulfonate | Varies | Rust-preventive films, corrosion inhibitors, metalworking |
Forms range from a clear-to-amber oil solution (in a carrier base oil) to a semi-solid, depending on base number and carrier. Confirm the active content, TBN and carrier on the purchase order.
Applications by sector
- Lubricant detergents & dispersants. Overbased calcium sulfonate neutralizes combustion and oxidation acids and keeps soot and deposits dispersed in engine and industrial oils.
- Rust preventives & corrosion inhibitors. Neutral and petroleum sulfonates form a water-displacing barrier film on steel — used in rust-preventive oils, temporary-protection coatings and metalworking fluids. See our corrosion inhibitors guide.
- Calcium-sulfonate-complex greases. Overbased calcium sulfonate is converted in situ to a calcite gel, giving greases with high dropping point, water resistance and inherent EP/anti-rust performance.
- Fuel & metalworking additives. Used for detergency and corrosion control in fuel and metal-treatment formulations.
Bulk supply and RFQ
RawSource sources calcium sulfonate to specification — neutral, overbased and petroleum grades, by TBN and carrier — in drums, totes and bulk. Send your target TBN, form and volume for a quote.
Regulatory & registration requirements
- TSCA (US):
- REACH (EU):
- EC number: 263-093-9
Source: EPA TSCA Inventory (July 2025 release) · ECHA CHEM — retrieved 2026-07-12
Frequently asked questions
What is calcium sulfonate used for?
Three main jobs: as a detergent/dispersant in lubricating oils (overbased grades neutralize acids and disperse soot), as a rust preventive and corrosion inhibitor on steel (it forms a water-displacing film), and as the thickener in calcium-sulfonate-complex greases. It is also used in fuel and metalworking additive packages.
What is the difference between neutral and overbased calcium sulfonate?
Neutral (low-base) calcium sulfonate has little reserve alkalinity and is used mainly for rust prevention and dispersancy. Overbased calcium sulfonate carries dispersed calcium carbonate that gives a high Total Base Number (TBN, typically ~300–400), providing the acid-neutralizing reserve needed in engine oils and the calcite network used to build complex greases.
What is TBN and why does it matter?
Total Base Number measures the reserve alkalinity of the sulfonate. Higher TBN means more capacity to neutralize acids and, for grease makers, more calcium carbonate available to form the thickener gel. Specify the TBN your formulation requires.
Is calcium sulfonate the same as calcium petroleum sulfonate?
Calcium petroleum sulfonate (representative CAS 61789-86-4) is the petroleum-derived form of calcium sulfonate. Synthetic calcium sulfonate is made from alkylbenzene feedstock. Both are calcium sulfonates; the choice depends on availability, color and the performance specification.
How is calcium sulfonate supplied and quoted?
It is supplied as an oil solution or semi-solid, specified by active content, TBN, carrier base oil and form, in drums, totes or bulk. Request a quote with your target grade and volume; the Certificate of Analysis governs the delivered specification.
Disclaimer
Information on this page is provided for general reference and compiled from authoritative public sources. Values are typical and are not a guaranteed specification; the Certificate of Analysis for the lot you purchase governs. Products are sold for industrial and professional use only. Nothing here is a medical, health, or efficacy claim. Always consult the current Safety Data Sheet before handling, and confirm regulatory status, classification and suitability for your application and jurisdiction.