Persistence of carbon dioxide corrosion inhibitors

This study used a polarization resistance (PR) technique in the long-term monitoring of corrosion rates for filmed electrodes in inhibitor-free electrolyte to assess the persistence of a broad range of batch treatment oil-fleld corrosion inhibitors. It was found that the persistence of an oil-field corrosion inhibitor is related to its tenacity of adsorption (reflected by its adsorption enthalpy) along with its affinity for hydrocarbon, as expressed by its octanol (C8H18O)-to-water distribution coefficient (P), obtained using the HyperChem molecular modeling program. Furthermore, a short-term electrochemical impedance spectroscopy monitoring program explored the interaction of hydrocarbons with inhibitor films, and the results generally correlated with the long-term PR data for the persistence of oil-field corrosion inhibitors. It was shown that this integrated approach provides valuable insights into the factors governing the persistence of oilfield corrosion inhibitors.