Because ethanol is a single, highly polar organic molecule that is completely soluble in water, its performance can differ from traditional hydrocarbon fuels that contain numerous organic molecules. As a result, handling, storage, use and performance of ethanol and ethanol-blended fuels can differ from conventional fuels.
Corrosion inhibitors for ethanol-blended fuels must be capable of providing performance in environments where dissolved water may be present. Salts and acid may also be present in the water, so the ethanol corrosion inhibitor must be capable of performing and protecting steel from corrosion under a range of environmental conditions.
When in contact with air during transportation and storage, ethanol will naturally react with oxygen in the air to form acidic compounds. The presence of these acidic compounds in ethanol can lead to corrosive wear of fuel pump and injector components as well as engine cylinder wear. To control ethanol quality, the acidity level of ethanol is measured by a specific pHe method, and an ethanol pHe specification ranging from 6.5 to 9.0 has been established.
The Nalco Water ethanol corrosion inhibitor is formulated with components that provide ferrous corrosion protection in gasoline containing ethanol and water. A second buffering component is present to control ethanol pHe and keep it in specification by neutralizing acidic compounds as they develop in stored ethanol.