Ultrahigh CO2/CH4 and CO2/N-2 adsorption selectivities on a cost-effectively L-aspartic acid based metal-organic framework
Ultrahigh CO2/CH4 and CO2/N-2 adsorption selectivities on a cost-effectively L-aspartic acid based metal-organic framework
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在经济高效的 L-天冬氨酸基金属有机框架上具有超高 CO2/CH4 和 CO2/N-2 吸附选择性
DOI：
10.1016/j.cej.2019.122074
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发表时间：
2019
影响因子：
15.1
通讯作者：
Xia Qibin
中科院分区：
文献类型：
--
作者：
Lv Daofei;Chen JiaYu;Yang Kexin;Wu Houxiao;Chen Yongwei;Duan Chongxiong;Wu Ying;Xiao Jing;Xi Hongxia;Li Zhong;Xia Qibin
利用多孔材料选择性吸附烟气或天然气中的二氧化碳是一种很有前途的减少二氧化碳排放和净化甲烷的方法。本文合成了一种l-天冬氨酸基微孔金属有机骨架（MIP-202），并研究了其对CO2/ ch4和CO2/ n2混合物的吸附分离性能。结果表明，MIP-202在298 K和100 kPa下具有超高的CO2/CH4选择性（CO2/CH4= 50/50和10/90时分别为72.9和241.5）和CO2/N2选择性（CO2/N2= 50/50和15/85时分别为1,950,000和2129.1）。通过亨利定律的计算和突破实验验证了其高选择性。Metropolis Monte Carlo模拟计算表明，具有较大极化率和四重矩的CO2倾向于占据极性较高的大型笼的孔壁，而极性较低的ch4或n2主要吸附在极性较低的小型笼的孔壁上，导致CO2/ ch4和CO2/ n2的分离选择性极高。MIP-202具有较低的co2吸附焓（17.2 ~ 30.7 kJ/mol），经过5次循环吸附实验后具有优异的持久可重复使用性，在298 K时易于解吸，水湿稳定性中等，在干湿so2气氛下稳定性好，配体成本低（36美元/kg）。以羟丙基纤维素（HPC）为粘结剂，采用挤压成型的方法制备了MIP-202挤出体，在常温常压下，MIP-202挤出体的co2吸收率为97.35%。这项工作表明，MIP-202是一种工业上有前途的材料，用于分离CO2/ ch4和CO2/ n2混合物。
Using porous materials to selectively adsorb CO2from flue gas or natural gas is a promising method for mitigating CO2emission and purifying methane. Here, we synthesized an L-aspartic acid based microporous metal-organic framework (MIP-202) and studied its adsorptive separation performance for CO2/CH4and CO2/N2mixtures. Results show that MIP-202 had ultrahigh CO2/CH4(72.9 and 241.5 for CO2/CH4= 50/50 and 10/90, respectively) and CO2/N2(1,950,000 and 2129.1 for CO2/N2= 50/50 and 15/85, respectively) IAST selectivities at 298 K and 100 kPa. The high selectivity was verified by the calculations of Henery’s law selectivity and breakthrough experiments. Metropolis Monte Carlo simulation calculations show that CO2with greater polarizability and quadruple moment tends to occupy the pore walls of large cages with higher polarity, while the less polar CH4or N2majorly being adsorbed in the pore walls of small cages with lower polarity, resulting in the ultrahigh CO2/CH4and CO2/N2separation selectivities. MIP-202 exhibits low CO2adsorption enthalpy (17.2–30.7 kJ/mol), superior persistent reusability after five cyclic adsorption experiments, easy desorption performance at 298 K, moderate water and moisture stability, good stability under dry and humid SO2atmosphere, and low ligand cost ($36/kg). MIP-202 extrudates were prepared by an extrusion molding method using hydroxypropyl cellulose (HPC) as the binder and they retained 97.35% CO2uptake of MIP-202 powder at room temperature and pressure. This work shows that MIP-202 is an industrially promising material for the separation of CO2/CH4and CO2/N2mixtures.