Thermodynamics Research Center / ThermoML | Journal of Chemical and Engineering Data

ABSTRACT

Deep eutectic solvents (DESs) have been extensively studied and applied to the absorption of acid gases. However, the absorption of nitric oxide (NO) by DES has rarely been reported. In this work, we found that NO can be absorbed by azole-derived DESs effectively and reversibly. A series of DESs with low viscosity based on tetrazolium (Tetz), triazole, imidazole as hydrogen bond donors (HBDs) and common ionic liquids as hydrogen bond acceptors (HBAs) were prepared. The absorption results showed that DESs based by tetrabutylphosphine chloride (P4444Cl) as HBA or Tetz as HBD exhibited the higher NO absorption. Notably, Tetz/P4444Cl DES exhibited the NO absorption of 2.10 and 1.01 mol/mol at 101.3 and 12 kPa partial pressure. In addition, the NO absorption capacity decreased continuously with the increasing temperature. The evaporation of Tetz/P4444Cl DES can be ignored during the absorption progress. The results of TGA measurment and regeneration experiments demonstrated that Tetz/P4444Cl possessed desirable thermostability and reusability. The absorption mechanism of NO by Tetz/P4444Cl was studied by FT-IR, 1H NMR and gaussian simulations. It was found that there was chemical interaction between NO and hydrogen-containing nitrogen atom of Tetz.