Effect of Amines as Corrosion Inhibitors for a Low Carbon Steel in Power Industry

Commonly used amines in power industry, including morpholine, DBU (1,8-diazabicyclo[5.4.0]undec-7-ene), and DMA (dimethylallylamine) were evaluated for their effect on AISI 1018 steel at 250oF. Samples were exposed to an autoclave containing amine added aqueous solution at pH of 9.5 for 1, 2, 4, 6, 8, and 12 hours. Morphology studies were carried using scanning electron microscope (SEM), phase analysis was done utilizing Fourier transform infrared spectroscopy (FTIR), and weight loss was performed to assess kinetics of oxidation. Control samples showed the highest metal dissolution rate. DBU showed the best performance in metal protection and SEM indicated the presence of a free-crack layer formed by fine particles in that set. FTIR showed that DBU apparently favored the formation of magnetite. It is believed that fine particles impede intrusion of aggressive ions into the metal surface by forming a barrier layer. FTIR demonstrated that DMA formed more oxyhydroxides, whereas morpholine presented magnetite to hematite transformation as early as 2 hours. SEM revealed that control and DMA produced acicular particles characteristic of oxyhydroxides while morpholine and DBU presented more equiaxed particles.

Grantor dc:publisher

University of North Texas

Year dc:date

2004

Author dc:creator

• Díaz, Jorge G.

Contributors dc:contributor

• Nasrazadani, Seifollah
• Foster, Phillip R.
• Mirshams, Reza
• Thiemer, Robert

• Amines.
• Corrosion resistant materials.
• Mild steel.
• amines
• magnetite
• hematite
• SEM
• FTIR
• corrosion
• lepidocrocite
• goethite
• DBU
• DMA
• morpholine

Statement dc:rights

• Public
• Copyright
• Díaz, Jorge G.
• Copyright is held by the author, unless otherwise noted. All rights reserved.

Language dc:language

English

Identifier

oclc: 70272396
https://digital.library.unt.edu/ark:/67531/metadc4666/
ark: ark:/67531/metadc4666

OAI identifier oai:identifier

info:ark/67531/metadc4666