Menu
Search
Filters
Close
Menu

51318-11027-Formation Mechanisms of Iron Oxide and Iron Sulfide at High Temperature in H2S Corrosion Environment

Picture for Formation Mechanisms of Iron Oxide and Iron Sulfide at High Temperature in H2S Corrosion Environment
Available for download

Previous studies have shown that, from 80°C to 200°C in an H2S only environment, magnetite forms as an inner layer while iron sulfides are found in the outer layer. A descriptive model for the formation mechanisms of magnetite and iron sulfide at high temperature is presented.

Product Number: 51318-11027-SG
Author: Shujun Gao / Bruce Brown / David Young / Srdjan Nesic / Marc Singer
Publication Date: 2018
Industry: Oil and Gas Production
$0.00
$20.00
$20.00

The mechanisms of corrosion of mild steel, and associated corrosion product formation, in high temperature sour environments are still largely unknown although they directly relate to pressing operating issues in the oil and gas industry. Previous studies have shown that, from 80°C to 200°C in an H2S only environment, magnetite forms as an inner layer while iron sulfides are found in the outer layer. Although magnetite is thermodynamically less stable than iron sulfide, it was always observed as a defined inner layer. In this work, experiments were conducted to investigate the formation mechanisms of magnetite and iron sulfide in a H2S environment at high temperature. The corrosion behavior of mild steel was first investigated in environments with and without H2S at 120oC, showing that magnetite is the dominant corrosion product layer in the initial stages of corrosion, due to a much faster kinetics of formation than iron sulfide (mackinawite). Magnetite is assumed to be responsible for the initial rapid decrease of the corrosion rate in this environment. In another experiment, the conversion of magnetite into mackinawite was investigated by exposing a preformed magnetite layer on an inert steel substrate (nickel) to an H2S environment. Consequently, it is postulated that Fe3O4 experiences a simultaneous and continuous process of formation at the steel/magnetite interface and conversion to mackinawite at the magnetite/mackinawite interface. A descriptive model for the formation mechanisms of magnetite and iron sulfide at high temperature is presented.

Key words: hydrogen sulfide, high temperature corrosion, iron sulfide, magnetite

The mechanisms of corrosion of mild steel, and associated corrosion product formation, in high temperature sour environments are still largely unknown although they directly relate to pressing operating issues in the oil and gas industry. Previous studies have shown that, from 80°C to 200°C in an H2S only environment, magnetite forms as an inner layer while iron sulfides are found in the outer layer. Although magnetite is thermodynamically less stable than iron sulfide, it was always observed as a defined inner layer. In this work, experiments were conducted to investigate the formation mechanisms of magnetite and iron sulfide in a H2S environment at high temperature. The corrosion behavior of mild steel was first investigated in environments with and without H2S at 120oC, showing that magnetite is the dominant corrosion product layer in the initial stages of corrosion, due to a much faster kinetics of formation than iron sulfide (mackinawite). Magnetite is assumed to be responsible for the initial rapid decrease of the corrosion rate in this environment. In another experiment, the conversion of magnetite into mackinawite was investigated by exposing a preformed magnetite layer on an inert steel substrate (nickel) to an H2S environment. Consequently, it is postulated that Fe3O4 experiences a simultaneous and continuous process of formation at the steel/magnetite interface and conversion to mackinawite at the magnetite/mackinawite interface. A descriptive model for the formation mechanisms of magnetite and iron sulfide at high temperature is presented.

Key words: hydrogen sulfide, high temperature corrosion, iron sulfide, magnetite

Product tags
Also Purchased
Picture for 06644 KINETICS OF IRON SULFIDE AND MIXED IRON
Available for download

06644 KINETICS OF IRON SULFIDE AND MIXED IRON SULFIDE/CARBONATE SCALE PRECIPITATION IN CO2/H2S CORROSION

Product Number: 51300-06644-SG
ISBN: 06644 2006 CP
Author: Wei Sun,Sankara Papavinasam, Srdjan Nesic
$20.00
Picture for Localized Corrosion of Mild Steel under Iron Sulfide Layers in CO2/H2S Environment
Available for download

51318-10990-Localized Corrosion of Mild Steel under Iron Sulfide Layers in CO2/H2S Environment

Product Number: 51318-10990-SG
Author: Saba Navabzadeh Esmaeely / Gheorghe Bota / Bruce Brown / Srdjan Nesic
Publication Date: 2018
$20.00

Mild steel specimens (API 5L X65) were pretreated to form a pyrrhotite layer on the surface using high temperature sulfidation in oil, then exposed to a range of aqueous CO2 and H2S corrosion environments, leading to initiation of localized corrosion.

 
Picture for 11266 Under Deposit Corrosion From Iron Sulfide
Available for download

11266 Under Deposit Corrosion From Iron Sulfide

Product Number: 51300-11266-SG
ISBN: 2011 11266 CP
Author: Sarah Standlee, K. Daniel Efird, Derek Spiller
Publication Date: 2011
$20.00
Categories
Industry
Recently viewed
Popular tags
View all

Association for Materials Protection and Performance

© AMPP All Rights Reserved.
Membership Terms of Content Use
Contact Customer Support