用于高效稳定吸附CO_(2)的胺基功能化MOF-808开发及机理  

Development and mechanism of amine-functionalized MOF-808 for efficient and stable CO_(2)adsorption

作　　者：沈遥 鲁恒霞 潘幸迪 叶杰旭[1,2] 赵景开 张士汉 SHEN Yao;LU Hengxia;PAN Xingdi;YE Jiexu;ZHAO Jingkai;ZHANG Shihan(Science and Education Integration College of Energy and Carbon Neutralization,Zhejiang University of Technology,Hangzhou 310014,China;College of Environment,Zhejiang University of Technology,Hangzhou 310014,China)

机构地区：[1]浙江工业大学能源与碳中和科教融合学院,浙江杭州310014 [2]浙江工业大学环境学院,浙江杭州310014

出　　处：《洁净煤技术》2024年第10期77-87,共11页Clean Coal Technology

基　　金：浙江省科技计划资助项目(2023C03156);国家自然科学基金资助项目(U23A20677,22022610,52400137);中国博士后科学基金资助项目(2024T170805,GZC20232363)。

摘　　要：胺基功能化金属有机骨架具有孔隙率高、CO_(2)吸附容量大、抗水性好的优点,被认为是适用于燃煤烟气CO_(2)捕集的吸附材料,但其表面胺基分子在高温脱附过程易发生团聚,导致吸附速率和吸附容量下降。采用物理浸渍将四乙烯五胺分子(TEPA)封装入MOF-808的孔道内,开发了一种胺基分子高度分散的胺基功能化吸附材料TEPA@MOF-808。TEPA@MOF-808的吸附容量相比MOF-808提高了2.15倍,吸附速率常数、吸附选择性分别提高了13%和498%,10次吸脱附循环后吸附容量仅下降10.9%,说明基于TEPA的胺基功能化策略可显著提高CO_(2)吸附性能和稳定性。热力学结果显示TEPA@MOF-808的等量吸附热仅为40 kJ/mol,小于普遍认为的化学吸附门槛,^(13)C固体核磁和原位红外表征结果进一步揭示了其以物理吸附为主的吸附机理。The amine-functionalized metal-organic frameworks are regarded as promising adsorbents for capturing CO_(2)from coal-fired flue gas due to their high porosity,large CO_(2)adsorption capacity,and good water resistance.However,the aggregation of surface amine molecules during high-temperature desorption processes leads to a drop in both adsorption rate and uptake.In this study,a novel aminefunctionalized adsorbent was developed by physically encapsulating tetraethylenepentamine molecules into the pores of MOF-808(TEPA@MOF-808)through a simple impregnation method.Compared to pristine MOF-808,TEPA@MOF-808 exhibited a 2.15-fold increase in CO_(2)adsorption uptake,along with enhancements of 13%in adsorption rate constant and 498%in adsorption selectivity.After 10 cycles,its adsorption uptake only decreased by 10.9%.Thermodynamic analysis revealed a low heat of adsorption of 40 kJ/mol,suggesting a physical adsorption mechanism.^(13)C SSNMR and in situ DRIFTS characterization further elucidated the CO_(2)physisorption mechanism of TEPA@MOF-808.

关 键 词：碳捕集 CO_(2)吸附 胺基功能化金属有机骨架 吸附动力学 

分 类 号：X701[环境科学与工程—环境工程] TQ424.3[化学工程]