Stringent environmental constraints imposed by government regulators upon the oil and gas producing industry has led to the need for new ‘greener’ chemistries, which have less environmental impact to be developed and employed. The environmental impact of a corrosion inhibitor is often defined by three tests, biodegradation, bioaccumulation and toxicity. All three criteria have limits that must be met for a chemical to be permitted for use, with different emphasis on each depending which regulator controls the waters. This has become the motivation for the research into modifying old chemistries and developing new ones.
Quaternary amines (quats) have been known for a long time as excellent corrosion inhibitors for their ability to form a film on the surface of the steel; however, their biotoxicity profile is not particularly acceptable to qualify them as "Green Corrosion Inhibitors". This work covers the structural modifications that have been imparted on quats to qualify them as green corrosion inhibitors with excellent corrosion protection.