Acetylenic Corrosion Inhibitors

The effectiveness of alpha hydroxy acetylenic compounds as corrosion inhibitors at iron and related surfaces has been shown to be due primarily to complex formation of the acetylenic with the metal surface. These complexes are believed to be stabilized by both pi and hydrogen bonding. It is also proposed that intermolecular attraction between acetylenics or nitrogen compounds, results in a charged multi-layer barrier at the ferrous surface, which further aids in the inhibition of acid corrosion. This concept can also be applied to the prevention of hydrogen embrittlement of steels, where acetylenic alcohols are also effective. The improvement of inhibitor performance, either with mixtures of alkynols or by formulation of acetylenics with nitrogen compounds, has been defined and measured by a Potentiation Ratio. This ratio is believed to be useful in evaluating corrosion inhibitor formulations with respect to the components in the formulation, and as a measure of inhibitor performance.