Performance Evaluation of Condiments as Environmentally Friendly Corrosion Inhibitors for Amine-Based Carbon Dioxide Absorption Process

Corrosion of process equipment and piping in the amine-based carbon dioxide (CO2) absorption process causes considerable expenditures for maintenance and repair. The addition of effective corrosion inhibitors to the amine solutions is a common practice for corrosion mitigation. Despite their inhibition effectiveness, those corrosion inhibitors used in the amine-based CO2 absorption process are not environmentally friendly and require costly waste handling and disposal. To reduce such cost and prepare for more stringent environmental regulations for chemical uses and disposal, this work investigated the feasibility of using condiments as environmentally friendly corrosion inhibitors in the amine-based CO2 absorption process. In this study, five condiments including powders of garlic, mustard, horseradish, onion and turmeric were selected and evaluated for their corrosion inhibition performance on carbon steel (CS1018) in the environment of 5.0 kmol/m3 aqueous solutions of monoethanolamine (MEA) saturated with dissolved CO2. The evaluation was carried out in corrosion experiments that employed cyclic and poteniodynamic polarization and electrochemical impedance spectroscopy for corrosion measurement and analysis. Results show that the powders of garlic, mustard, horseradish, onion showed great promise for corrosion reduction in both MEA-CO2 and MEA-CO2-oxygen (O2) solutions. They performed well with inhibition efficiencies in the range of 80- 95% even at elevated temperatures and the presence of process contaminants (i.e., chloride and oxalate) which were found to slightly affect the inhibition performance. These four condiments were proved to be mixed-type (anodic and cathodic) corrosion inhibitors that protected the metal surface by undergoing endothermic physical and chemical adsorption with the Langmuir adsorption isotherm. Sulfur, nitrogen, phosphorus functional groups were the primary contributors to the inhibition effectiveness. Unlike these four condiments, the powder of turmeric was not promising as it yielded lower inhibition efficiency and induced pitting corrosion for most tested conditions.

Name thesis:degree_name

Master of Applied Science (MASc)

Level thesis:degree_level

Master's

Discipline thesis:degree_discipline

Engineering - Process Systems

Grantor dc:publisher

Faculty of Graduate Studies and Research, University of Regina

Year dc:date.issued

2018

Author dc:creator

• Sekkappan, Sockalingam

Advisor dc:contributor.advisor

• Veawab, Amornvadee

Committee members dc:contributor.committeemember

• Young, Stephanie
• Aroonwilas, Adisorn

Language dc:language.iso

en

DOI

https://doi.org/10.82465/5044

OAI identifier oai:identifier

oai:uregina.scholaris.ca:10294/8429