Title
Measurement and prediction of oxygen solubility in post-combustion CO2 capture solvents
Author
Buvik, V.
Bernhardsen, I.M.
Figueiredo, R.V.
Vevelstad, S.J.
Goetheer, E.L.V.
van Os, P.J.
Knuutila, H.K.
Publication year
2021
Abstract
This work aims to understand oxygen solubility in pure and aqueous amine solvents for CO2 capture. Commercially available dissolved oxygen sensors were studied to evaluate whether these can be used for measuring oxygen solubility in the carbon capture processes. It also aims to understand the possible discrepansies from realistic concentrations of oxygen when using a dissolved oxygen sensor. Two independent measurement principles were used for this purpose, both electrochemical and optical. Furthermore, a Winkler titration method was used to aid the validation of the sensors as well as understanding salting-out effects. A simple model for predicting oxygen solubility in CO2-loaded ethanolamine solutions was made, which also has potential for predicting oxygen solubility in other loaded amine solutions. The results of the study show that dissolved oxygen sensors may be applied for measurement of oxygen concentrations in amine solutions and that different amines and different concentrations in water only show small variations in oxygen solubility. The sensors may also be used in CO2-loaded mine solutions, but here the increased conductivity of the solution may give a higher measured concentration of oxygen, than it is in reality. In ethanolamine, the consumption of oxygen is faster than the mass transfer of oxygen from gas to liquid phase, giving lower concentrations of oxygen than it should be in absence of a chemical reaction between oxygen and amine.
Subject
Amine solvents
CO2absorption
Dissolved oxygen sensor
Oxidative degradation
Oxygen removal
Oxygen solubility
Sustainable Chemical Industry
Industrial Innovation
To reference this document use:
http://resolver.tudelft.nl/uuid:e8d77049-a562-4a89-a79a-91547d46144e
DOI
https://doi.org/10.1016/j.ijggc.2020.103205
TNO identifier
955355
Publisher
Elsevier, Amsterdam
ISSN
1750-5836
Source
International Journal of Greenhouse Gas Control, 104 (104)
Document type
article