Aria Kahyarian

Mechanism of Cathodic Reactions in Acetic Acid Corrosion of Iron and Mild Steel

The mechanism of the cathodic reaction in acetic acid corrosion of iron and API X65 mild steel was investigated in mildly acidic sodium chloride electrolytes. The behavior of the charge transfer co...

CO2 corrosion of mild steel

The current state of understanding of CO 2 corrosion as related to internal corrosion of oil and gas pipelines made from mild steel is reviewed. The review covers the effects of basic physicochemical phenomena underlying CO 2 corrosion, such as surface electrochemistry, homogenous aqueous chemistry, mass transfer, and formation of protective corrosion product layers. It then addresses some of the main “complicating factors,” such as multiphase flow, additional aqueous species, hydrocarbon composition, inhibition, and localized corrosion. Additional challenges seen in the field are presented at the end.

34 – Mathematical modeling of uniform CO2 corrosion

The uniform carbon dioxide corrosion is one of the most widely studied subjects in corrosion science and engineering. Numerous corrosion rate–predictive models have been developed and reported in the literature over the past few decades. In this chapter, these models are grouped in four categories of empirical, semiempirical, elementary mechanistic, and comprehensive mechanistic, based on the mathematical methods and the calculation approach used to quantify the underlying physiochemical processes. With the focus on the mechanistic models, some key publications are reviewed, and the advantages and limits for each type of the models are discussed. Furthermore, a collection of the relevant mathematical expressions as well as solution methods required to construct the mechanistic models is provided.

Technical Note: Electrochemistry of CO2 Corrosion of Mild Steel: Effect of CO2 on Cathodic Currents

The common understanding of aqueous CO2 corrosion mechanism considers carbonic acid as an electroactive species. The direct reduction of carbonic acid on a steel surface is believed to be the cause of the higher corrosion rates of mild steel, as compared to that observed in strong-acid solutions with the same pH. However, in-depth quantitative analyses based on comprehensive mechanistic models, developed in recent years, have challenged this idea. In an attempt to provide explicit experimental evidence for the significance of direct reduction of carbonic acid in CO2 corrosion of mild steel, the charge transfer controlled cathodic currents in CO2 saturated solutions were investigated in the present study. The experiments were conducted on three different surfaces: Type 316L stainless steel, pure iron, and API 5L X65 mild steel, in order to examine the possible effect of alloying impurities on the kinetics and the mechanism of cathodic currents. The experimental polarization curves showed that at a constant...

7 – CO2 corrosion of mild steel

The current state of understanding of CO 2 corrosion as related to internal corrosion of oil and gas pipelines made from mild steel is reviewed. The review covers the effects of basic physicochemical phenomena underlying CO 2 corrosion, such as surface electrochemistry, homogenous aqueous chemistry, mass transfer, and formation of protective corrosion product layers. It then addresses some of the main “complicating factors,” such as multiphase flow, additional aqueous species, hydrocarbon composition, inhibition, and localized corrosion. Additional challenges seen in the field are presented at the end.

CO 2 corrosion of mild steel

The current state of understanding of CO 2 corrosion as related to internal corrosion of oil and gas pipelines made from mild steel is reviewed. The review covers the effects of basic physicochemical phenomena underlying CO 2 corrosion, such as surface electrochemistry, homogenous aqueous chemistry, mass transfer, and formation of protective corrosion product layers. It then addresses some of the main “complicating factors,” such as multiphase flow, additional aqueous species, hydrocarbon composition, inhibition, and localized corrosion. Additional challenges seen in the field are presented at the end.