摘要
离子液体是一种新型溶剂,由于其具有挥发性极低、稳定性高、结构(性质)可调等优点备受关注。调整离子液体的结构,使其成为烟气SO2的高效吸收剂,且能够同时满足:离子液体可再生、SO2容易回收和资源化。本文介绍了离子液体的特性,用于吸收SO2离子液体的结构特点,有效脱除SO2功能化离子液体的判断方法;论述了离子液体吸收SO2的研究进展,包括胍类离子液体、咪唑类离子液体、醇胺类离子液体、季类离子液体、季铵类离子液体等吸收SO2;探讨了离子液体吸收烟气中SO2过程中存在的问题,包括离子液体的黏度、稳定性及烟气中其他物质(如O2、水分、CO2、烟尘)对吸收的影响;分析了离子液体用于脱硫过程能耗高的原因及提高离子液体吸收SO2的吸收能力的方法;最后尝试提出离子液体吸收烟气SO2研究进一步的发展方向。
Due to their extremely low vapor pressure, high stability and designability of structure, ionic liq- uids （ILs） are considered as a new kind of solvents. After functionalization for the specific task of trapping SO2, ILs are called functional ILs or task specific ILs and become absorbers for trapping SO2 from flue gas, which can realize the regeneration of absorbents and recovery of SO2 and make SO2 a resource of sulfur. The article intro- duces the properties of ILs, and how to differentiate functional from normal ILs and how to make ILs functional. The article reviews the studies on absorption of SO2 by functional ILs, including guanidinium based functional ILs, imidazolium based functional ILs, hydroxyl ammonium based functional ILs, phosphonium based functional ILs, and quaternary ammonium based functional ILs. We discussed the present problems on the absorption of SO2 from flue gas, such as the viscosity of ILs during absorption of SO2, the high cost of IL, energy consumption during ab- sorption of SO2 while exploring how to improve the absorption capacity of SO2 and the stability of ILs when ab- sorbing SO2, as well as the effect of other species （such as O2, water moisture, CO2 and dust） in flue gas. At last, possible future developments in the absorption of SO2 from flue gas were analyzed and outlined.
基金
国家自然科学基金项目(21176020
21306007)
中央高校科研业务费项目(ZY1305)
关键词
功能化离子液体
吸收
SO2
烟气
functional ionic liquids
absorption
SO2
flue gas
