用于CH4/N2分离的多吸附位点超微孔MOF

doi:10.11949/0438-1157.20241213

摘要/Abstract

摘要：

开发用于纯化非常规天然气中甲烷（CH₄）的吸附剂，对能源和环境的可持续发展具有重要意义。然而，CH₄和N₂的物理化学性质极为相似，这使得高性能吸附剂的设计成为巨大的挑战。以低极性芳香族咪唑环配体1H-苯并咪唑-5-羧酸构建超微孔金属有机框架材料（Ni-BZZA），有望实现CH₄/N₂混合的高效分离。该材料孔表面具有密集的氮杂环和氧原子，可作为CH₄的强结合位点。Ni-BZZA的超微孔道为CH₄提供了强大的约束性作用，在298 K和0.1 MPa下呈现出优异的CH₄吸附量（39.1 cm³·g^-1）和CH₄/N₂（体积比50/50）选择性（8.6）。在模拟工业条件下进行的穿透实验证实Ni-BZZA可以高效分离CH₄/N₂混合物。Ni-BZZA具有优异的CH₄吸附量和CH₄/N₂选择性，说明其在非常规天然气中富集CH₄方面具有极大的潜力。

关键词: 金属有机框架, 吸附剂, 天然气, 选择性, 吸附, 分离

Abstract:

The development of adsorbents for purifying methane (CH₄) from unconventional natural gas is of great significance for the sustainable development of energy and environment. However, the physical and chemical properties of CH₄ and N₂ are extremely similar, making the design of high-performance adsorbents a daunting challenge. Herein, an ultra-microporous metal-organic framework (Ni-BZZA) was constructed using a low polarity aromatic imidazole ring ligand 1H-benzimidazole-5carboxylic acid for efficient separation of CH₄/N₂ mixtures. The pore surface of Ni-BZZA has dense nitrogen heterocycles and accessible oxygen atoms that can serve as strong binding sites for CH₄. The ultramicroporous of Ni-BZZA provide strong constraints for CH₄. The synergistic effect of pore size and pore surface chemistry results in excellent CH₄ uptake (39.1 cm³·g^-1) and CH₄/N₂ (50/50, vol) selectivity (8.6) of Ni-BZZA at 298 K and 0.1 MPa. Breakthrough experiment conducted under simulated industrial conditions has confirmed that Ni-BZZA can efficiently separate CH₄/N₂ mixture. The excellent CH₄ uptake and CH₄/N₂ selectivity of Ni-BZZA indicate its great potential for enriching CH₄ in unconventional natural gas.

Key words: metal-organic framework, adsorbent, natural gas, selectivity, adsorption, separation

中图分类号:

TQ 028.1

郭彭涛, 王婷, 薛波, 应允攀, 刘大欢. 用于CH₄/N₂分离的多吸附位点超微孔MOF[J]. 化工学报, 2025, 76(5): 2304-2312.

Pengtao GUO, Ting WANG, Bo XUE, Yunpan YING, Dahuan LIU. Ultramicroporous MOF with multiple adsorption sites for CH₄/N₂ separation[J]. CIESC Journal, 2025, 76(5): 2304-2312.

图/表 9

图1 (a) Ni-BZZA的二级结构单元；(b)沿轴c观察的Ni-BZZA晶体结构

Fig.1 (a) Secondary building blocks of Ni-BZZA; (b) Crystal structure of Ni-BZZA viewed along c axis

图2 (a) 刚合成和活化后Ni-BZZA的PXRD图谱；(b) Ni-BZZA的SEM图像；(c) Ni-BZZA的热重分析曲线；(d) 195 K下Ni-BZZA的CO2吸附-脱附等温线（插图：Ni-BZZA的孔径分布）(1 Å=0.1 nm)

Fig.2 (a) PXRD patterns of as-synthesized and activated Ni-BZZA; (b) SEM images of Ni-BZZA; (c) Thermogravimetric analysis curves of Ni-BZZA; and (d) CO2 adsorption-desorption isotherms of Ni-BZZA at 195 K (Inset: pore size distribution of Ni-BZZA)

图3 298 K和273 K下Ni-BZZA的CH4和N2单组分吸附-脱附等温线

Fig.3 Single-component adsorption isotherms of CH4 and N2 in Ni-BZZA at 298 K and 273 K

表1 298 K、1 bar下Ni-BZZA与其他吸附剂的CH4吸附量对比

Table1 Comparison of CH4 uptake of Ni-BZZA with other adsorbents at 298 K and 1 bar

吸附剂	晶体密度/(g·cm^-3)	吸附量/(cm³·g^-1)	体积吸附量/(cm³·cm^-3)	文献
Ni-BZZA	1.31	39.1	51.20	本研究
Al-CDC	1.27	32.0	40.64	[33]
Co₃(C₄O₄)₂(OH)₂	2.18	9.0	19.81	[29]
STAM-1	1.47	14.2	20.87	[34]
NKMOF-8-Me	1.37	39.5	54.11	[35]
MIL-160	1.12	10.5	11.76	[36]
Al-FUM-Me	1.04	27.2	28.29	[37]
Ni(BTC)(PIZ)	1.04	36.3	38.06	[38]
Co-MA-BPY	1.42	20.6	29.25	[39]
CAU-10	1.16	16.6	19.26	[36]
Ni(OAc)₂L	0.81	25.7	20.82	[22]

图4 (a) Ni-BZZA对CH4和N2的吸附热；(b) Ni-BZZA与其他吸附剂的吸附热对比

Fig.4 (a) Adsorption heat of Ni-BZZA for CH4 and N2; (b) Comparison of adsorption heat Qst of Ni-BZZA with other adsorbents

表2 Dual-site Langmuir-Freundlich方程拟合298 K下Ni-BZZA的CH4和N2的吸附等温线参数

Table2 Parameters for fitting adsorption isotherms of CH4 and N2 on Ni-BZZA at 298 K using dual-site Langmuir-Freundlich equation

Gas	$N A m a x$ /(cm³·g^-1)	b_A/bar^-1	V_A	$N B m a x$ /(cm³·g^-1)	b_B/bar^-1	V_B	R²
CH₄	30.98924	3.457645	1.025724	34.41176	0.776073	1.055484	0.9999
N₂	15.94589	0.691774	1.888699	8.010242	3.280542	1.146546	0.9999

表2 Dual-site Langmuir-Freundlich方程拟合298 K下Ni-BZZA的CH4和N2的吸附等温线参数

Table2 Parameters for fitting adsorption isotherms of CH4 and N2 on Ni-BZZA at 298 K using dual-site Langmuir-Freundlich equation

Gas	$N A m a x$ /(cm³·g^-1)	b_A/bar^-1	V_A	$N B m a x$ /(cm³·g^-1)	b_B/bar^-1	V_B	R²
CH₄	30.98924	3.457645	1.025724	34.41176	0.776073	1.055484	0.9999
N₂	15.94589	0.691774	1.888699	8.010242	3.280542	1.146546	0.9999

图5 Dual-site Langmuir-Frendlich方程拟合的Ni-BZZA的CH4 (a)和N2 (b)吸附等温线

Fig.5 Dual-site Langmuir-Freundlich equations fit for CH4 (a) and N2 (b) adsorption isotherms of Ni-BZZA

图6 (a) 298 K下Ni-BZZA的CH4/N2（体积比50/50、30/70和10/90）IAST选择性；(b) Ni-BZZA与其他吸附剂的IAST选择性和CH4吸附量对比

Fig.6 (a) CH4/N2 (50/50, 30/70 and 10/90, vol) IAST selectivity of Ni-BZZA at 298 K; (b) Comparison of IAST selectivity and CH4 uptake of Ni-BZZA with other adsorbents

图7 (a) 在298 K下Ni-BZZA的CH4/N2（体积比50/50）混合物的穿透曲线；(b) Ni-BZZA与其他吸附剂的CH4穿透吸附量对比

Fig.7 (a) Breakthrough curves of CH4/N2 (50/50, vol) mixtures of Ni-BZZA at 298 K; (b) Comparison of CH4 breakthrough uptake of Ni-BZZA with those of other adsorbents

参考文献 42

1	Chang M, Ren J H, Wei Y, et al. Discovery of a scalable metal-organic framework with a switchable structure for efficient CH₄/N₂ separation[J]. Chemistry of Materials, 2023, 35(11): 4286-4296.
2	Wang S M, Shivanna M, Yang Q Y. Nickel-based metal-organic frameworks for coal-bed methane purification with record CH₄/N₂ selectivity[J]. Angewandte Chemie International Edition, 2022, 61(15): e202201017.
3	马蕾, 张飞飞, 宋志强, 等. 金属有机骨架材料用于吸附分离CH₄和N₂的研究进展[J]. 化工进展, 2021, 40(9): 5107-5117.
	Ma L, Zhang F F, Song Z Q, et al. Development of metal-organic frameworks in adsorptive separation of CH₄-N₂ [J]. Chemical Industry and Engineering Progress, 2021, 40(9): 5107-5117.
4	Wu Y Q, Weckhuysen B M. Separation and purification of hydrocarbons with porous materials[J]. Angewandte Chemie International Edition, 2021, 60(35): 18930-18949.
5	Zhao Y L, Zhang X, Li M Z, et al. Non-CO₂ greenhouse gas separation using advanced porous materials[J]. Chemical Society Reviews, 2024, 53(4): 2056-2098.
6	Lelieveld J, Klingmüller K, Pozzer A, et al. Effects of fossil fuel and total anthropogenic emission removal on public health and climate[J]. Proceedings of the National Academy of Sciences of the United States of America, 2019, 116(15): 7192-7197.
7	Yu Y X, Shang M Y, Kong L T, et al. Influence of ligands within Al-based metal-organic frameworks for selective separation of methane from unconventional natural gas[J]. Chemosphere, 2023, 321: 138160.
8	Xing G Y, Cong S Z, Wang B, et al. A high-performance N₂-selective MXene membrane with double selectivity mechanism for N₂/CH₄ separation[J]. Small, 2024, 20(14): 2309360.
9	Kim J, Maiti A, Lin L C, et al. New materials for methane capture from dilute and medium-concentration sources[J]. Nature Communications, 2013, 4: 1694.
10	Zhang Z, Poulter B, Knox S, et al. Anthropogenic emission is the main contributor to the rise of atmospheric methane during 1993—2017[J]. National Science Review, 2021, 9(5): nwab200.
11	Qadir S, Li D F, Gu Y M, et al. Experimental and numerical investigations on the separation performance of [Cu(INA)₂] adsorbent for CH₄ recovery by VPSA from oxygen-bearing coal mine methane[J]. Chemical Engineering Journal, 2021, 408: 127238.
12	郑卫, 马文君. 变压吸附气体分离技术的应用进展[J]. 当代化工研究, 2024(15): 11-13.
	Zheng W, Ma W J. Overview of the application progress of pressure swing adsorption gas separation technology[J]. Modern Chemical Research, 2024(15): 11-13.
13	Qian Z L, Zhou Y W, Yang Y, et al. Methane recovery from low-grade unconventional natural gas by the integrated mode of the conventional/improved vacuum pressure swing adsorption processes[J]. Fuel, 2023, 331: 125717.
14	Guo Y, Hu J L, Liu X W, et al. Scalable solvent-free preparation of [Ni₃(HCOO)₆] frameworks for highly efficient separation of CH₄ from N₂ [J]. Chemical Engineering Journal, 2017, 327: 564-572.
15	Li J R, Kuppler R J, Zhou H C. Selective gas adsorption and separation in metal-organic frameworks[J]. Chemical Society Reviews, 2009, 38(5): 1477-1504.
16	Nandanwar S U, Corbin D R, Shiflett M B. A review of porous adsorbents for the separation of nitrogen from natural gas[J]. Industrial & Engineering Chemistry Research, 2020, 59(30): 13355-13369.
17	刘伟, 田林宇, 王宪飞, 等. 金属有机框架材料分离碳四烃的研究进展[J]. 现代化工, 2020, 40(3): 16-21.
	Liu W, Tian L Y, Wang X F, et al. Study progress in separation of C₄ hydrocarbons by metal-organic frameworks[J]. Modern Chemical Industry, 2020, 40(3): 16-21.
18	Jiang Y, Jia S J, Liu X Q, et al. Selective adsorption of ethane over ethylene through a metal-organic framework bearing dense alkyl groups[J]. Separation and Purification Technology, 2022, 295: 121330.
19	Wang J, Zhang Y, Zhang P X, et al. Optimizing pore space for flexible-robust metal-organic framework to boost trace acetylene removal[J]. Journal of the American Chemical Society, 2020, 142(21): 9744-9751.
20	Cadiau A, Adil K, Bhatt P M, et al. A metal-organic framework-based splitter for separating propylene from propane[J]. Science, 2016, 353(6295): 137-140.
21	Li T, Jia X X, Chen H, et al. Tuning the pore environment of MOFs toward efficient CH₄/N₂ separation under humid conditions[J]. ACS Applied Materials & Interfaces, 2022, 14(13): 15830-15839.
22	Kivi C E, Gelfand B S, Dureckova H, et al. 3D porous metal-organic framework for selective adsorption of methane over dinitrogen under ambient pressure[J]. Chemical Communications, 2018, 54(100): 14104-14107.
23	肖思杰, 廖小诺, 郭志奋, 等. 多孔材料吸附分离甲烷氮气研究进展[J]. 云南化工, 2023, 50(11): 1-4.
	Xiao S J, Liao X N, Guo Z F, et al. Research progress of porous material for adsorption separation of methane and nitrogen[J]. Yunnan Chemical Technology, 2023, 50(11): 1-4.
24	Zhang F F, Shang H, Zhai B L, et al. Thermodynamic-kinetic synergistic separation of CH₄/N₂ on a robust aluminum-based metal-organic framework[J]. AIChE Journal, 2023, 69(6): e18079.
25	Qadir S, Gu Y M, Ali S, et al. A thermally stable isoquinoline based ultra-microporous metal-organic framework for CH₄ separation from coal mine methane[J]. Chemical Engineering Journal, 2022, 428: 131136.
26	Hu J L, Sun T J, Liu X W, et al. Separation of CH₄/N₂ mixtures in metal-organic frameworks with 1D micro-channels[J]. RSC Advances, 2016, 6(68): 64039-64046.
27	Tan Y X, He Y P, Zhang J. Temperature-/pressure-dependent selective separation of CO₂ or benzene in a chiral metal-organic framework material[J]. ChemSusChem, 2012, 5(8): 1597-1601.
28	Myers A L, Prausnitz J M. Thermodynamics of mixed-gas adsorption[J]. AIChE Journal, 1965, 11(1): 121-127.
29	Li L Y, Yang L F, Wang J W, et al. Highly efficient separation of methane from nitrogen on a squarate-based metal-organic framework[J]. AIChE Journal, 2018, 64(10): 3681-3689.
30	Nguyen P T K, Nguyen H T D, Pham H Q, et al. Synthesis and selective CO₂ capture properties of a series of hexatopic linker-based metal-organic frameworks[J]. Inorganic Chemistry, 2015, 54(20): 10065-10072.
31	Guo P T, Ying Y P, Liu D H. One scalable and stable metal-organic framework for efficient separation of CH₄/N₂ mixture[J]. ACS Applied Materials & Interfaces, 2024, 16(6): 7338-7344.
32	Shi Q, Wang J, Shang H, et al. Effective CH₄ enrichment from N₂ by SIM-1 via a strong adsorption potential SOD cage[J]. Separation and Purification Technology, 2020, 230: 115850.
33	Chang M, Zhao Y J, Liu D H, et al. Methane-trapping metal-organic frameworks with an aliphatic ligand for efficient CH₄/N₂ separation[J]. Sustainable Energy & Fuels, 2020, 4(1): 138-142.
34	Chang M, Zhao Y J, Yang Q Y, et al. Microporous metal-organic frameworks with hydrophilic and hydrophobic pores for efficient separation of CH₄/N₂ mixture[J]. ACS Omega, 2019, 4(11): 14511-14516.
35	Chang M, Wang F, Wei Y, et al. Separation of CH₄/N₂ by an ultra-stable metal-organic framework with the highest breakthrough selectivity[J]. AIChE Journal, 2022, 68(9): e17794.
36	Huang Z H, Hu P, Liu J, et al. Enhancing CH₄/N₂ separation performance within aluminum-based metal-organic frameworks: influence of the pore structure and linker polarity[J]. Separation and Purification Technology, 2022, 286: 120446.
37	Chang M, Yan T A, Wei Y, et al. Enhancing CH₄ capture from coalbed methane through tuning van der Waals affinity within isoreticular Al-based metal-organic frameworks[J]. ACS Applied Materials & Interfaces, 2022, 14(22): 25374-25384.
38	Chen Y, Wang Y, Wang Y, et al. Improving CH₄ uptake and CH₄/N₂ separation in pillar-layered metal-organic frameworks using a regulating strategy of interlayer channels[J]. AIChE Journal, 2022, 68(11): e17819.
39	Liu X W, Gu Y M, Sun T J, et al. Water resistant and flexible MOF materials for highly efficient separation of methane from nitrogen[J]. Industrial & Engineering Chemistry Research, 2019, 58(44): 20392-20400.
40	Chang M, Ren J H, Yang Q Y, et al. A robust calcium-based microporous metal-organic framework for efficient CH₄/N₂ separation[J]. Chemical Engineering Journal, 2021, 408: 127294.
41	Wang Q M, Shen D M, Bülow M, et al. Metallo-organic molecular sieve for gas separation and purification[J]. Microporous and Mesoporous Materials, 2002, 55(2): 217-230.
42	Yang J F, Tang X, Liu J Q, et al. Down-sizing the crystal size of ZK-5 zeolite for its enhanced CH₄ adsorption and CH₄/N₂ separation performances[J]. Chemical Engineering Journal, 2021, 406: 126599.

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用于CH₄/N₂分离的多吸附位点超微孔MOF

Ultramicroporous MOF with multiple adsorption sites for CH₄/N₂ separation

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