Evaluation of Performance of Corrosion Inhibitors Using Adsorption Isotherm Models: An Overview
Ekemini Ituen *
African Centre of Excellence in Oilfield Chemicals Research, Institute of Petroleum Studies, University of Port Harcourt, Nigeria
Onyewuchi Akaranta
African Centre of Excellence in Oilfield Chemicals Research, Institute of Petroleum Studies, University of Port Harcourt, Nigeria and Department of Pure and Industrial Chemistry, University of Port Harcourt, Nigeria
Abosede James
Department of Pure and Industrial Chemistry, University of Port Harcourt, Nigeria
*Author to whom correspondence should be addressed.
Abstract
Adsorption isotherm models are an important tool for describing interaction of corrosion inhibitors with metal surfaces which they are aimed to protect. In this paper, key adsorption isotherms used in corrosion inhibition studies have been reviewed. We have examined how some deductions on the nature of metal-corrosion inhibitor interactions are obtained from certain parameters and interpreted to characterize the adsorption of the corrosion inhibitors and their mechanisms of inhibition. More attention is paid to their applications and the useful information that may be derived from them than on their background and derivation. Efforts have also been made to identify some limitations (where applicable) and/or discrepancies in usage of some models in reporting experimental findings. Informed by some inconsistencies observed from some literature reports, critical suggestions on appropriate approaches to collection and processing of data for fitting into these isotherms have been made. This paper will be a beneficial secondary source of information to readers and invaluable reference material to experts and future researchers in the subject area.
Keywords: Active site, adsorption isotherm, corrosion inhibitor, equilibrium constant, molecular interaction parameter, monolayer, size parameter