Absorption of Nitric Oxide in Simulated Flue Gas by Azole-Based
Hydrophobic Deep Eutectic Solvents
Abstract
Functional hydrophobic deep eutectic solvents composed with azoles as
hydrogen bond donors, and [N8881]Cl and [N8881]Br as hydrogen
bond acceptors were designed and synthesized to absorb low
concentrations NO. The good hydrophobicity reduces the cost of operating
effectively. Moreover, the capacity of 10 vol % NO absorption by
Im-[N8881]Cl DES can reach 3.91 mol NO / mol Im at 40 oC. Besides,
Im-[N8881]Cl DES can be regenerated, and the absorption capacity of
NO by the regenerated Im-[N8881]Cl DES shows no significant loss for
at least 5 recycles. FTIR and 1H NMR were used to verify the mechanism.
The results indicate that there is chemical interaction between NO and
Im-[N8881]Cl DES and the main chemical active sites are N (2) and N
(5) on Im by forming NONOates. This series of hydrophobic, efficient and
reversible NO absorbents may provide a new idea for NO capture
technique.