Abstract
An optimized approach of CO2 fixation in Ca2+/Mg2+-rich aqueous solutions using insoluble amine as an enhancing medium was reported. Apparent basicity was verified to be an effective indicator for the selection and optimization of organic amine systems and finally the diisobutylamine + n-octanol system was selected to enhance the carbonation reactions of CO2 in an artificial Ca2+/Mg2+-rich solution. In our experiments, when the volume ratio of insoluble organic phase to aqueous one was 2:1 and the reaction temperature was 28 °C, 92% of Ca2+ and 80% of Mg2+ could be converted to calcium and magnesium carbonate precipitates within 5 min of reaction with the bubbling-in of CO2. The organic amine system could be regenerated by using carbide slag as the regeneration agent and could still show attractive enhancement performances after 7 rounds of carbonation-regeneration experiments. In this way, the CO2 capture and sequestration was realized within one single process, with value-added Ca/Mg carbonates being the byproducts. In view of the vast availability of Ca2+/Mg2+-rich aqueous solutions and the feasible technical coordination with desalination industry, this novel process may have a good application potential in the future.
Highlights
Converted into carbonates on temporal scales of engineering when the pH level of reaction system could be raised steadily by employing something as a pH regulator[18]
In our built-up process, when alkaline amine extractants are added into a Ca2+/Mg2+-rich aqueous system, the equilibrium of CO2 dissolution in water will be broken
High-quality carbonate byproducts are obtained, and the amine phase can be regenerated via some alkaline minerals like carbide slag or aqueous ammonia
Summary
Converted into carbonates on temporal scales of engineering when the pH level of reaction system could be raised steadily by employing something as a pH regulator[18]. In the typical carbonation experiments with diisobutylamine + n-octonal as the enhancement system, the organic phase and aqueous phase were mixed at the volume ratio of 2:1 and the reactions were carried out at 28 °C.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.