基于冰模板法的多孔地聚合物微结构及其对CO_(2)的吸附性能

Microstructures and CO_(2)adsorption performance of porous geopolymer prepared by ice templating method

【目的】研究冰模板法制备的多孔地聚合物对CO_(2)的吸附性能,从而提供一种制备CO_(2)吸附剂的新方法,进一步拓宽地聚合物的应用范围。【方法】以水玻璃、矿渣为基本原材料,利用冰模板法制备多孔地聚合物,通过压汞法和N2吸附/脱附法表征其孔结构,采用热分析仪研究其对CO_(2)的吸附性能。【结果】冰模板法制备的多孔地聚合物孔径呈三峰型分布,尺寸能从纳米到几微米再到几百微米变化,介孔结构呈现层状结构;多孔地聚合物对CO_(2)的吸附量达到4.07 mmol/g,吸附过程符合准二级动力学模型,其中物理吸附量和化学吸附量分别占总吸附量的7.28%和92.72%。【结论】与其他CO_(2)吸附剂相比,用冰模板法制备的多孔地聚合物具有较高的CO_(2)吸附量,其结合地聚合物本身耐高温和化学稳定性好的特性,可以实现在特定环境条件下的应用,是一种非常有潜力的CO_(2)吸附材料。

[Purposes]This study investigates the CO_(2)adsorption performance of porous geopolymers prepared using the ice templating method,aiming to provide a novel approach for the preparation of CO_(2)adsorbents and further broaden the application scope of geopolymers.[Methods]Using water glass and slag as fundamental raw materials,porous geopolymers were synthesized through the ice templating technique.The pore structure was characterized using mercury porosimetry and N2 adsorption/desorption analysis.The CO_(2)adsorption performance was investigated employing thermal analysis instrumentation.[Findings]Porous geopolymers prepared using the ice templating method exhibit a trimodal distribution of pore sizes,ranging from nanometers to a few micrometers,and up to several hundred micrometers.The mesoporous structure demonstrates a layered arrangement.The CO_(2)adsorption capacity of the porous geopolymers reaches 4.07 mmol/g.The adsorption process follows a pseudo-second-order kinetic model,with physical and chemical accounted for 7.28%and 92.72%of the total adsorption respectively.[Conclusions]Compared to other CO_(2)adsorbents,the porous geopolymers produced through the ice templating method exhibit a higher CO_(2)adsorption capacity.Considering the inherent high-temperature resistance and excellent chemical stability of geopolymers,these materials hold the potential for applications in specific environmental conditions.They represent a highly promising CO_(2)adsorption material with notable prospects.