Molecular sieve-supported ionic liquids as efficient adsorbents for CO2 capture

Amino ethyl-3-methylimidazolium tetrafluoroborate, [NH(3)e-mim] [BF4], amino ethyl-3-methylimidazolium tetrafluoroborate, [OHe-mim][BF4], and 2-hydroxyethylammonium lactate, [HOEAm], were selected and supported onto a variety of molecular sieves, NaY, USY, SAPO-34 and MCM-41, to prepare supported ionic liquids. It was found that [NH(3)e-mim][BF4]/NaY showed an excellent CO2 adsorption performance, with an adsorption capacity of 0.11 mmol CO2 g(-1). In this study, the optimal adsorption conditions and recyclability of [NH(3)e-mim][BF4]/NaY were investigated. The results showed that [NH(3)e-mim][BF4]/NaY showed good CO2 adsorption under the conditions of 20 degrees C and 20 % loading of the IL. By vacuum heating, the CO2 adsorption capacity reached 0.45 mmol CO2 g(-1) in the fifth adsorption run but was reduced to 0.29 mmol CO2 g in the tenth run. The structure and characterization of [NH(3)e-mim][BF4]/NaY were examined by FT-IR, XRD, SEM and TG-DSC. The TG-DSC results showed that the thermostability of NH(3)e-mim][BF4]/NaY was good below 50 degrees C.