TY - JOUR
T1 - Direct Air Capture of CO2Using Solvents
AU - Custelcean, Radu
N1 - Publisher Copyright:
© 2022 Annual Reviews Inc.. All rights reserved.
PY - 2022
Y1 - 2022
N2 - Large-scale deployment of negative emissions technologies (NETs) that permanently remove CO2from the atmosphere is now considered essential for limiting the global temperature increase to less than 2°C by the end of this century. One promising NET is direct air capture (DAC), a technology that employs engineered chemical processes to remove atmospheric carbon dioxide, potentially at the scale of billions of metric tons per year. This review highlights one of the two main approaches to DAC based on aqueous solvents. The discussion focuses on different aspects of DAC with solvents, starting with the fundamental chemistry that includes the chemical species and reactions involved and the thermodynamics and kinetics of CO2binding and release. Chemical engineering aspects are also discussed, including air-liquid contactor design, process development, and technoeconomic assessments to estimate the cost of the DAC technologies. Various solvents employed in DAC are reviewed, from aqueous alkaline solutions (NaOH, KOH) to aqueous amines, amino acids, and peptides, along with different solvent regeneration methods, from the traditional thermal swinging to the more exploratory carbonate crystallization with guanidines or electrochemical methods.
AB - Large-scale deployment of negative emissions technologies (NETs) that permanently remove CO2from the atmosphere is now considered essential for limiting the global temperature increase to less than 2°C by the end of this century. One promising NET is direct air capture (DAC), a technology that employs engineered chemical processes to remove atmospheric carbon dioxide, potentially at the scale of billions of metric tons per year. This review highlights one of the two main approaches to DAC based on aqueous solvents. The discussion focuses on different aspects of DAC with solvents, starting with the fundamental chemistry that includes the chemical species and reactions involved and the thermodynamics and kinetics of CO2binding and release. Chemical engineering aspects are also discussed, including air-liquid contactor design, process development, and technoeconomic assessments to estimate the cost of the DAC technologies. Various solvents employed in DAC are reviewed, from aqueous alkaline solutions (NaOH, KOH) to aqueous amines, amino acids, and peptides, along with different solvent regeneration methods, from the traditional thermal swinging to the more exploratory carbonate crystallization with guanidines or electrochemical methods.
KW - alkaline base
KW - amino acid
KW - aqueous solvent
KW - carbon dioxide removal
KW - negative emissions technologies
UR - http://www.scopus.com/inward/record.url?scp=85132050087&partnerID=8YFLogxK
U2 - 10.1146/annurev-chembioeng-092120-023936
DO - 10.1146/annurev-chembioeng-092120-023936
M3 - Review article
C2 - 35303770
AN - SCOPUS:85132050087
SN - 1947-5438
VL - 13
SP - 217
EP - 234
JO - Annual Review of Chemical and Biomolecular Engineering
JF - Annual Review of Chemical and Biomolecular Engineering
ER -