Technical Specifications
| Property | Unit | Typical Value | Test Method |
|---|---|---|---|
| Appearance | Customizable (sheet / granular / powder / needle) | Visual | |
| Purity | % | 99.9 | GC |
| Melting Point | °C | 98 | ASTM E324-23 |
| Moisture Content | % | 0.06 | ASTM D95 |
| Ash Content | % | 0.03 | ASTM C561-23 |
| pH | 5.5 | — | |
| Solubility | Oil / water / alcohol | — |
* Typical values from batch production. Batch-specific COA available on request.
Technical content reviewed by the CheMost additives team · Specifications last reviewed
Molecular Structure
Molecular structure · benzotriazole
C₆H₅N₃ (MW 119.12)
1H-Benzotriazole — a fused benzene/triazole ring; the basic ring nitrogens bond to copper, building a self-limiting passivation film.
What Is Benzotriazole (BTA)?
CheMost-BTA is high-purity 1H-benzotriazole (99.9% GC) — the standard metal deactivator and corrosion inhibitor for copper, copper alloys and other non-ferrous (yellow) metals. It is a discrete pure compound (C₆H₅N₃, a fused benzene–triazole ring) supplied as a solid in customizable physical forms and soluble in oil, water and alcohol.
Unlike the sulfonate rust inhibitors, which protect ferrous metals by forming an adsorbed oil film, benzotriazole works on copper and yellow metals by chemistry: its ring nitrogens bond to the copper surface to build a thin, self-limiting Cu–BTA passivation film. That film both prevents corrosion and tarnish of the copper part and suppresses the copper-catalysed oxidation that would otherwise shorten the oil’s life — which is why BTA is the copper passivator in most finished lubricant and rust-preventive packages.
As a nitrogen heterocycle, benzotriazole is also mildly volatile, so it can act as a vapour-phase corrosion inhibitor (VCI), protecting copper and aluminium surfaces it is not in direct contact with — useful in enclosed equipment and storage.
How Benzotriazole Works
Cu–BTA passivation film
The triazole ring nitrogens chemisorb onto copper and copper alloys, forming a thin, tightly bound Cu–benzotriazole complex that passivates the surface and blocks corrosion and tarnish.
Metal deactivation (anti-oxidation)
By capping copper surfaces, BTA stops dissolved copper from catalysing oil oxidation — extending oil life. This is its role as a metal deactivator in finished lubricants, working alongside the antioxidants.
Vapour-phase protection (VCI)
Its volatility lets benzotriazole protect copper and aluminium surfaces in the vapour space of enclosed equipment, where a non-volatile film former cannot reach.
No inorganic-salt residue
As an organic heterocycle it leaves no inorganic dry residue, and works at very low treat — a clean, efficient copper passivator across oil- and water-based systems.
Applications
CheMost-BTA is used as the copper/yellow-metal deactivator in formulations targeting the duties below:
Lubricants & metalworking fluids
Copper-corrosion protection and metal deactivation in industrial oils, gear and hydraulic oils, greases and metalworking fluids — protecting bronze and copper components and suppressing copper-catalysed oxidation.
Rust-preventive oils & antifreeze
The copper passivator in rust-preventive oils and in engine coolants/antifreeze, where copper and brass radiator components must be protected.
Cooling-water & industrial systems
Widely used to protect copper and yellow metals in cooling-water systems and other industrial fluids; also a building block for many derivative inhibitors.
Application performance depends on the finished formulation. CheMost can provide REACH/TSCA and market-registration documentation support on request.
Treat Rate
The data sheet specifies the product but not a per-application dosage, so the figure below is indicative, derived from the chemistry and our formulating experience — confirm the final level.
First-order estimate. As a metal deactivator, benzotriazole is used at very low levels — roughly 0.01–0.3% (tens to a few hundred ppm) — just enough to form the passivation monolayer on the copper surfaces present. Above that, extra BTA gives little additional benefit.
The right level scales with the copper/yellow-metal area to be protected and the rest of the package; in finished lubricants BTA is dosed alongside the antioxidants and the ferrous-metal rust inhibitors. The exact level depends on the system and the target copper-corrosion result.
Treat rates are indicative, not fixed dosages. CheMost can provide formulation and treat-rate support on request.
Formulating With BTA — Complementary Additives
Benzotriazole covers copper and yellow metals; a complete corrosion package pairs it with additives that protect ferrous metals and extend oil life:
Sulfonate rust inhibitors
Sodium/barium petroleum sulfonates and barium/calcium DNNS protect ferrous metals with an adsorbed film, while BTA passivates copper and yellow metals — together they give multi-metal protection.
Antioxidants
By deactivating copper, BTA removes a powerful oxidation catalyst, so phenolic and aminic antioxidants work harder for longer — a classic antioxidant + metal-deactivator pairing.
Thiadiazole metal deactivators
Thiadiazole-type deactivators broaden multi-metal coverage; combining triazole and thiadiazole chemistries protects a wider range of non-ferrous metals.
Rust-preventive sulfonates
In rust-preventive oils, BTA adds copper/brass protection on top of the barium sulfonate’s ferrous-metal film for parts containing mixed metals.
Physical Forms & Solubility
CheMost-BTA is a high-purity solid (99.9% by GC) offered in customizable physical forms — sheet-like, granular, powdery, needle-like or hemispherical particles — to suit your handling and dissolution needs. It is soluble in oil, water and alcohol, which lets it be incorporated into oil-based lubricants, water-based coolants and solvent systems alike. The melting point is 98 °C, moisture ≤0.06%, ash ≤0.03% and pH 5.5 (full data in the Technical Specifications above).
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 forms & packaging
Customizable particle form (sheet / granular / powder / needle) and packaging.
Formulation support
Treat-rate and metal-deactivator formulation guidance from our technical team.
Packaging & Supply
CheMost-BTA 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
20 kg polywoven bag.
Minimum order
By bag or pallet — contact us for your quantity.
Incoterms
FOB · CIF · EXW, to suit your freight arrangement.
Loading ports
All major Chinese ports.
Frequently Asked Questions
What is benzotriazole used for?
Benzotriazole (BTA, CAS 95-14-7) is a corrosion inhibitor and metal deactivator that protects copper, copper alloys and other yellow metals. In lubricants and rust-preventive oils it passivates copper components and suppresses copper-catalysed oil oxidation; it is also used in antifreeze/coolants, cooling-water systems, and as a building block for derivative inhibitors.
How does benzotriazole work?
Its triazole-ring nitrogens bond to the copper surface and build a thin, self-limiting Cu–benzotriazole complex film. That passivation layer blocks corrosion and tarnish and, by capping the copper, stops dissolved copper from catalysing oxidation of the oil. Because it is mildly volatile, BTA can also protect copper in the vapour phase as a VCI.
What treat rate of benzotriazole is used?
As a metal deactivator, BTA is used at very low levels — typically about 0.01–0.3% (tens to a few hundred ppm) — enough to form the passivation monolayer on the copper present. More than that gives little extra benefit. The exact level depends on the copper/yellow-metal area and the rest of the package.
Is benzotriazole soluble in oil and water?
Yes — CheMost-BTA (99.9% purity) is soluble in oil, water and alcohol, so it can be used in oil-based lubricants, water-based coolants and solvent systems. It is supplied as a solid in customizable forms (sheet, granular, powder, needle) with a melting point of 98 °C.
How is it supplied, and how fast can I get a sample?
It is supplied as a solid in 20 kg polywoven bags with a 36-month shelf life, and shipped worldwide. As a manufacturer and sourcing partner (Est. 2013), CheMost answers sample and quotation requests within 12 hours.