关键词: 1-氨丙基-3-甲基咪唑溴盐, CO₂, 离子液体, 载体, 吸收

Abstract: CO₂ was absorbed by 1-aminopropyl-3-methylimidazolium bromine([APMIm][Br])as chemical reaction. The absorbents were prepared by supporting ionic liquids on porous silica gel through the impregnation-evaporation method, and pore structure and absorption capacity were characterized with specific surface pore adsorption apparatus and thermogravimetric analysis, respectively. CO₂ absorption was conducted under the following conditions: 10% to 50% of ionic liquids loading, 303.15 K to 323.15 K of temperature, and 10%, 30%, 50% of CO₂ in mixed gas. The results suggested that absorption rate was fastest when film thickness of ionic liquids on the silica gel was 86 nm, and was little affected by the change of CO₂ concentration and temperature. Equilibrium absorption amount reached 80% of the theoretical uptake in 50% CO₂ system, and was reducing with increasing temperature. However, absorption rate and capacity decreased obviously as film thickness of ionic liquid exceeded 230 nm. The properties of supported ionic liquid absorbent remained unchanged after recycling three times, showing the prospect of industrial use.

Key words: [APMIm][Br], carbon dioxide, ionic liquids, support, absorption