多孔材料捕集烟道气中二氧化碳研究进展

Research progress on porous materials for capturing carbon dioxide from flue gas

化石燃料燃烧引起的CO_(2)排放是全球气候变暖、极端天气频发的重要原因之一。目前中国一次能源以化石能源为主,CO_(2)排放仍居高位。使用低成本、低能耗的CO_(2)捕集方法是缓解上述情况发生的一种有效手段。与醇胺溶液吸收法相比,吸附法具有能耗低、对设备损害小、循环稳定性良好等优点,但同时它也存在吸附材料制备过程繁杂、成本高的缺陷。因此,亟待寻找一种成本低廉、CO_(2)吸附性能优异的吸附材料实现对CO_(2)的高效捕集。以多孔材料为出发点介绍了理想吸附材料应具有的性能,重点论述了烟气中水蒸气、SO_(2)等成分对于多孔材料CO_(2)吸附性能的影响以及多孔材料CO_(2)吸附性能的改进方式。多孔材料具有比表面积大、孔径可调等优势,其中硅基介孔材料和活性炭材料价格低廉,MOFs材料功能多样,这些特征使得多孔材料被广泛应用于CO_(2)捕集领域。值得注意的是,分子筛和硅基介孔材料对水蒸气敏感程度大,MOFs材料虽受水蒸气影响较分子筛小,但其在低压下吸附容量低,制备成本也比较高,活性炭材料同样也存在吸附容量低等缺点。因此,各种多孔材料还需不断改性以提高其吸附性能,目前大部分多孔材料的改性方式集中在孔隙结构调控和表面改性。未来研究还需深入探究多孔材料吸附CO_(2)的内在机制以及表面改性与孔隙结构的协同调控等。

The CO_(2)emission caused by fossil fuel combustion is one of the important reasons for global warming and extreme weather.At present,fossil fuel is still the primary energy in China and CO_(2)emission remains high.The use of low-cost and energy-efficient CO_(2)capture methods can effectively alleviate the occurrence of above situation.Compared with the alcohol amine solution absorption method,the adsorption method has the advantages of low energy consumption,less damage to the equipment and excellent cycle stability,etc.However,the adsorption materials usually involve a complex preparation process and the cost is high.Therefore,it is urgent to find a kind of new adsorption material with low cost and excellent CO_(2)adsorption performance to achieve an efficient CO_(2)capture.In this study,the properties of ideal porous adsorption materials are introduced,the influence of other gases such as water vapor and SO_(2)in the flue gas on the CO_(2)adsorption performance of porous materials,and the ways to improve the CO_(2)adsorption performance of porous materials are mainly discussed.Porous materials have the advantages of large specific surface area,and adjustable pore size,etc.,among which the silicon-based mesoporous materials and activated carbon have low prices,and the MOFs materials have various functions.These characteristics make porous materials widely used in the field of CO_(2)capture.However,it is worth noting that the molecular sieves and silicon-based mesoporous materials are highly sensitive to water vapor.The MOFs materials are less affected by water vapor than the molecular sieves,but their adsorption capacity is relatively low under low pressure and their preparation cost is relatively high.Activated carbon materials also have disadvantages such as low adsorption capacity.Therefore,various porous materials need to be constantly modified to improve their adsorption performance,and most of the modification methods of porous materials focus on pore structure regulation and surface modification.Future research needs to further explore the internal mechanism of CO_(2)adsorption by porous materials and the synergistic regulation of surface modification and pore structure.