Capturing CO 2 from the flue gas in the power plant is an important measure to realize the low-carbon combustion of the fossil energy. This paper presents a novel technique which combines traditional methods of the chemical absorption, the physical adsorption and the membrane absorption. The ionic liquid ([TEPA][MIm]) is utilized to improve the CO 2 absorption performance and reduce the energy consumption. While the porous skeleton (ZIF-8) is added to the ionic liquid to reduce the viscosity while introducing the physical adsorption. Moreover, the hydrophobic ceramic membrane is utilized as the separation interface between the gas phase and the liquid phase, which can avoid the entrainment and overflow of the liquid phase while increasing the specific surface area. In terms of the material preparation and the characterization, the addition of ZIF-8 does not destroy the original chemical composition of [TEPA][MIm]. The average contact angle of the hydrophobic ceramic membrane is 140.55°, and the failure temperature is greater than 400 K, which conforms to the application situation of the power plant. In terms of the CO 2 capture and the desorption performance, the maximum CO 2 capture amount reaches 2.03 mol/mol. The temperature of complete desorption is 70 °C. Furthermore, the capture performance after five cycles can reach 80 % of the initial performance. The performance is better than that of the CO 2 capture technology utilizing the traditional monoethanolamine solution.
The efficient capture of carbon dioxide (CO 2 ) by porous ionic liquids (PILs) has become one of the important ways to deal with the greenhouse effect and enhance environmental protection. In order to enhance the CO 2 capture efficiency of PILs, 2 amino-functional ionic liquids (ILs) were synthesized in deionized water: tetraethylenepentamine-2-methylimidazole ([TEPA][MIm]) and diethylenetriamine-2-methylimidazole ([DETA][MIm]). 2 zeolite imidazolidin-8 frames (ZIF-8-W and ZIF-8-M) were prepared in methanol and deionized water. The performance of the material was verified through FT-IR infrared spectroscopy, TGA-DTG curves, XRD spectra, adsorption desorption curves, and corrosive changes. Based on this, the porous ionic liquid ZIF-8-W/[TEPA][MIm] with the best performance and ZIF-8-W with the best environmental friendliness were successfully constructed. The chemical reaction mechanism of CO 2 in PILs were explored. The results showed that the thermogravimetric temperature of all materials was greater than 370 K, and the difference in adsorption capacity between ZIF-8-W and ZIF-8-M was only about 36.3 ml/g, the maximum mass change rates of the two ILs after immersion in ceramic and stainless steel tubes for 7 days were only 0.78 % and 0.29 %, respectively. On the premise of ensuring fluidity, the maximum capture capacity of ZIF-8-W/[TEPA][MIm] for pure CO 2 reached 2.22 mol/mol PILs, and the maximum capture capacity for CO 2 in artificial flue gas reached 2.03 mol/mol PILs, which was 21.9 % and 31.6 % higher than the maximum capture capacity of pure ionic liquids, respectively. When [TEPA][MIm] in PILs reacts with CO 2 , it conforms to the characteristics of “zwitterions”.
危险品化学品经营许可证（带存储）