TY - JOUR
T1 - Unraveling the Role of Metal Oxide Catalysts in the CO2 Desorption Process from Nonaqueous Sorbents: An Experimental Study Carried out with 13C NMR
AU - Bhatti, Umair Hassan
AU - Ienco, Andrea
AU - Peruzzini, Maurizio
AU - Barzagli, Francesco
N1 - KAUST Repository Item: Exported on 2021-11-11
Acknowledgements: For the financial support, the authors thank the ICCOM Institute of the National Research Council.
PY - 2021/11/9
Y1 - 2021/11/9
N2 - The CO2 desorption process from a CO2-saturated nonaqueous sorbent, 2-(2-aminoethoxy)ethanol (DGA) in diethylene glycol monomethyl ether (DEGMME), was investigated in the absence and presence of four different metal oxides, namely, V2O5, TiO2, WO3, and ZnO, aiming at identifying acid catalysts with the potential to reduce the energy demand for sorbent regeneration. The desorption performances of the DGA-DEGMME solutions with and without catalysts were evaluated in terms of CO2 desorption rate, overall CO2 desorbed, and thermal energy consumption. The desorption mechanism was understood by the 13C NMR speciation study of the solutions during the regeneration experiments. As a result, metal oxide catalysts, depending on the number and types of acidic sites on their surface, can accelerate the carbamate breakdown and the subsequent CO2 release. In particular, WO3 and TiO2 can be considered good candidates for implementation in CO2 capture processes with nonaqueous sorbents, as they greatly improved the desorption performance, and their structures remain unchanged before and after use. The combination of nonaqueous sorbents with catalysts, here reported for the first time, provides an effective strategy that could inspire the design of advanced sorbents for energy-efficient CO2 capture.
AB - The CO2 desorption process from a CO2-saturated nonaqueous sorbent, 2-(2-aminoethoxy)ethanol (DGA) in diethylene glycol monomethyl ether (DEGMME), was investigated in the absence and presence of four different metal oxides, namely, V2O5, TiO2, WO3, and ZnO, aiming at identifying acid catalysts with the potential to reduce the energy demand for sorbent regeneration. The desorption performances of the DGA-DEGMME solutions with and without catalysts were evaluated in terms of CO2 desorption rate, overall CO2 desorbed, and thermal energy consumption. The desorption mechanism was understood by the 13C NMR speciation study of the solutions during the regeneration experiments. As a result, metal oxide catalysts, depending on the number and types of acidic sites on their surface, can accelerate the carbamate breakdown and the subsequent CO2 release. In particular, WO3 and TiO2 can be considered good candidates for implementation in CO2 capture processes with nonaqueous sorbents, as they greatly improved the desorption performance, and their structures remain unchanged before and after use. The combination of nonaqueous sorbents with catalysts, here reported for the first time, provides an effective strategy that could inspire the design of advanced sorbents for energy-efficient CO2 capture.
UR - http://hdl.handle.net/10754/673279
UR - https://pubs.acs.org/doi/10.1021/acssuschemeng.1c04026
U2 - 10.1021/acssuschemeng.1c04026
DO - 10.1021/acssuschemeng.1c04026
M3 - Article
SN - 2168-0485
JO - ACS Sustainable Chemistry & Engineering
JF - ACS Sustainable Chemistry & Engineering
ER -