J 2024

Unraveling the mechanism and the role of hydrogen bonds in CO<sub>2</sub> capture by diluent-free amine sorbents through a combination of experimental and theoretical methods

MANCA, Gabriele, Francesco BARZAGLI, Jakub NAGY, Markéta MUNZAROVÁ, Maurizio PERUZZINI et. al.

Basic information

Original name

Unraveling the mechanism and the role of hydrogen bonds in CO<sub>2</sub> capture by diluent-free amine sorbents through a combination of experimental and theoretical methods

Authors

MANCA, Gabriele, Francesco BARZAGLI, Jakub NAGY (703 Slovakia, belonging to the institution), Markéta MUNZAROVÁ (203 Czech Republic, guarantor, belonging to the institution), Maurizio PERUZZINI and Andrea IENCO

Edition

Fuel, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, ELSEVIER SCI LTD, 2024, 0016-2361

Other information

Language

English

Type of outcome

Článek v odborném periodiku

Field of Study

10403 Physical chemistry

Country of publisher

United Kingdom of Great Britain and Northern Ireland

Confidentiality degree

není předmětem státního či obchodního tajemství

References:

Impact factor

Impact factor: 7.400 in 2022

Organization unit

Faculty of Science

UT WoS

001301822200001

Keywords in English

Carbon storage; CO (2) capture; Hydrogen bonds; Reaction mechanisms; Diluent-free sorbents

Tags

Tags

International impact
Změněno: 10/9/2024 14:13, Mgr. Pavla Foltynová, Ph.D.

Abstract

V originále

The utilization of water-lean and non-aqueous amine sorbents is regarded as an appealing approach to reduce the energy costs of CO2 capture via liquid sorbents. However, significant research is still needed to achieve the technological maturity required for industrial-scale implementation. Here, we present a detailed experimental and computational analysis at the molecular level of CO2 capture by dipropylamine (DPA) as a case study to deepen our understanding of the mechanisms governing CO2 absorption by liquid secondary amines that can be used without any additional diluent. CO2 uptake with pure DPA was investigated, and the species produced over time were determined by NMR and FT-IR spectroscopy. In particular, the NMR analysis revealed the formation of carbamic acid at high CO2/DPA ratios. A detailed DFT investigation explained the mechanism of the reaction revealing a dynamic evolution in product distribution as CO2 loading increases. At low CO2 loadings, adducts with at least four DPA molecules are formed, ultimately leading to the carbamate/ammonium ionic pair stabilized through H-bonding interactions with DPA moieties. Conversely, at higher CO2 levels some stabilizing DPA molecules of ionic pair are required for the CO2 activation, resulting in the formation of carbamic acid. A reasonable mechanism for the evolution of product distribution is provided, and the main steps of the mechanistic picture are depicted and commented on. The dependence of carbamate and carbamic acid on the availability of hydrogen bond donors and acceptors in solution is also highlighted.