Extended Understanding of Inhibition Mechanism of New Corrosion Inhibitor via Electrochemical Measurements and X-Ray Photoelectron Spectroscopy (XPS)

摘要

Traditionally, phosphorous based corrosion inhibitors are applied to prevent corrosion occurring in heat exchangers of cooling tower operations. It is well known that a protective coating rich in phosphate material protects a surface from corrosion by forming a uniform layer with thickness in micrometer range. Although, efficient in corrosion prevention, there is detrimental environmental impact due to discharge of phosphorous downstream of application. Significant research is sustained to design and identify alternative chemistries to address the phosphorous discharge concerns. A novel corrosion inhibitor was developed and successfully applied in the field and an extended understanding of the inhibition mechanism was investigated. In this paper, a combination of electrochemical and surface studies was used to shed light upon the corrosion inhibition mechanism through which the novel corrosion inhibitor protects the surface. X-ray Photoelectron Spectroscopy (XPS) was used to evaluate the protective coating layer at the surface. This study focuses on understanding the impact of reaction time and flow regime on protective coating formation and composition. The XPS results were correlated with the corrosion rates obtained via the electrochemical data.