Overview
Metal deactivators are used to passivate copper and other non-ferrous metal surfaces in lubricating oil systems. Dissolved copper ions are potent catalysts for oil oxidation; even trace quantities can dramatically accelerate oxidative degradation. Triazole and benzotriazole derivatives form stable chelate complexes with copper ions and adsorb on metal surfaces, preventing further dissolution. They also provide corrosion protection for yellow metal components such as bronze bushings, brass fittings, and copper heat exchanger tubes within lubricated systems. These additives are used at low treat rates (typically 0.01–0.1 wt%) in engine oils, turbine oils, hydraulic fluids, and metalworking fluids.
| Chemistry | TBN (mgKOH/g) | Copper Corrosion |
|---|---|---|
| Triazole Derivatives Metal Deactivator | 160–185 | ≤1b |
| Methylbenzotriazole Derivatives Metal Deactivator | 120–170 | ≤1b |