|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Characterization of Minerals, Metals, and Materials
||Characterization of Iron Oxide Scale Formed in Naphthenic Acid Corrosion
||Peng Jin, Winston Robbins, Gheorghe Bota, Srdjan Nesic
|On-Site Speaker (Planned)
Naphthenic acid (NAP) corrosion is one of the major concerns for corrosion engineers in refineries. Traditionally, the iron sulfide (FeS) layer, formed when sulfur compounds in crudes corrode the metal, is expected to be protective and limit the NAP corrosive effects. However, no relationship has been found between protectiveness and the characteristics of FeS layer. In this study, lab scale tests with model sulfur compounds and NAP replicated corrosive processes of refineries with real crude fractions behavior. The morphology and chemical composition of layers were analyzed with Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). These high resolution microscopy techniques revealed the presence of an iron oxide (Fe3O4 or magnetite) layer on metal surfaces under FeS layers. Its presence was correlated with the NAP acid activity during the experiments. It is postulated that the formation of the Fe3O4 layer resulted from the decomposition of iron naphthenate at high temperatures.
||Planned: A print-only volume