作者：王金秀, 洪锦德

作者单位：复旦大学 先进材料实验室，上海 200438

关键词：物理吸附;表征;沸石;孔径

摘要：

孔径是沸石分子筛的一个重要物性常数，与沸石在吸附分离、催化等应用有密切关系。因此，准确测定、分析其孔径分布具有重要意义。采用N₂、Ar和CO₂为吸附质气体，通过物理吸附法测定5A沸石分子筛的孔径分布，详细研究吸附质气体、吸附温度以及计算方法对孔径分布的影响。结果表明：采用Ar或CO₂作为吸附质，并使用Saito-Foley（SF）或非限定域密度泛函理论（NLDFT）计算方法可以准确分析5A沸石分子筛的微孔孔径分布。该实验结果和讨论将有助于进一步加深对微孔孔径分析的理解，为在实验中选择合适的测量方法提供参考。

Research on pore size characterization of 5A zeolite molecular sieves by physisorption method
WANG Jinxiu, HUNG Chinte
Laboratory of Advanced Materials, Fudan University, Shanghai 200438, China
Abstract: The pore size is an important physical constant of zeolite molecular sieve, which is closely related to the application of zeolite in adsorption, separation and catalysis. Therefore, it is of great significance to accurately measure and analyze the pore size distribution. The pore size distribution of 5A zeolite molecular sieves was characterized based on the physisorption method by using N₂, Ar and CO₂ as the adsorbent gases. The influences of adsorbent gas, adsorption temperature and calculation method on the pore size distribution were studied in detail. The results showed that using Ar or CO₂ as adsorbent and Saito-Foley (SF) or non-local density functional theory (NLDFT) calculation method can accurately analyze the micropore distribution of 5A zeolite molecular sieves. The results and discussion will be helpful to further understand the micropore size analysis and provide guidance for selecting appropriate measurement method in the experiment.
Keywords: physisorption;characterization;zeolite;pore size
2021, 47(9):1-6  收稿日期: 2020-10-09;收到修改稿日期: 2020-11-24
基金项目: 国家重点研发计划战略性国际科技创新合作重点专项（2018YFE0201700）
作者简介: 王金秀(1980-),女,山东蒙阴县人,工程师,博士,主要从事多孔材料的表征及储能应用
参考文献
[1] 杨建利, 晏志军, 李栋墚, 等. 焙烧法水热合成5A沸石分子筛[J]. 工业催化, 2007, 15(10): 64-66
[2] 王鹏, 刘京雷, 张胜中, 等. 结构化5A分子筛吸附床结构及工艺参数对N₂/H₂吸附性能的影响[J]. 化工学报, 2020, 7(71): 3114-3122
[3] 曾国治, 王睿, 库尔, 等. 5A沸石分子筛低温变压吸附CO₂/CH₄实验研究[J]. 广州化工, 2019, 10(47): 56-58
[4] 方怡, 黄奋生, 孙艳, 等. 5A分子筛分离提纯混合己烷中的正己烷[J]. 石油和化工设备, 2018, 9(21): 59-60
[5] 刘芝平, 张嫱嫱, 马静红, 等. 正构烷烃在介孔5A沸石中的吸附[J]. 化工学报, 2014, 3(65): 934-941
[6] 李灿, 马福秋, 李健, 王海斌, 等. 5A分子筛基吸附剂制备及脱除H₂S性能研究[J]. 中国环保产业, 2017, 5: 31-34
[7] SING K S W, WILLIAMS R T. The use of molecular probes for the characterization of nanoporous adsorbents[J]. Particle & Particle Systems Characterization, 2004, 21(2): 71-79
[8] RAVIKOVITCH P I, VISHNYAKOV A, RUSSO R, et al. Unified approach to pore size characterization of microporous carbonaceous materials from N₂, Ar, and CO₂ adsorption isotherms[J]. Langmuir, 2000, 16: 2311-2320
[9] 杨正红, THOMMES M. 体吸附法进行孔径分析进展--密度函数理论(DFT)及蒙特卡洛法(MC)的应用[J]. 中国粉体工业, 2009, 6: 36-42
[10] 贾双珠, 吴林媛, 陈炷霖, 等. 微介孔材料的孔结构分析表征[J]. 分析测试技术与仪器, 2019, 3(25): 141-147
[11] DONG Q B, SONG Z N, ZHOU F L, et al. Ultrathin, fine-tuned microporous coating modified 5A zeolite for propane/ propylene adsorptive separation[J]. Microporous and Mesoporous Materials, 2019, 281: 9-14
[12] DU X D, LIU Z J, CUI Q, et al. Effect of secondary pore distribution on adsorption diffusion performance of n-hexane on 5 A zeolite pellets[J]. Journal of Southeast University (English Edition), 2011, 27(3): 284-289
[13] XIONG R J, XICOHTENCATL R B, ZHANG L D, et al. Thermodynamics, kinetics and selectivity of H₂ and D₂ on zeolite 5A below 77K[J]. Microporous and Mesoporous Materials, 2018, 264: 22-27
[14] HORVATH G, KAWAZOE K. Method for calculation of effective pore size distribution in molecular sieve carbon[J]. Journal of Chemical Engineering of Japan, 1983, 16(6): 470-475
[15] HORVATH G. Energetic interactions in phase and molecular level pore characterization in nano-range[J]. Colloids & Surface A: Physicochemical and Engineering Aspects, 1998, 141(3): 295-304
[16] EVERETT D H, POWL J C. Adsorption in slit-like and cylindrical micropores in the henry's law region. A model for the microporosity of carbons[J]. Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases, 1976, 72: 619-636
[17] SAITO A, FOLEY H C. Curvature and parametric sensitivity in models for adsorption in micropores[J]. AIChE Journal, 1991, 37(3): 429-436
[18] LASTOSKIE C, GUBBINS K E, QUIRKE N. Pore size distribution analysis of microporous carbons: a density functional theory approach[J]. The Journal of Physical Chemistry, 1993, 97: 4786-4796
[19] OLIVIER J P. Modeling physical adsorption on porous and nonporous solids using density functional theoryJournal of porous materials[J]. Journal of Porous Materials, 1995, 2(1): 9-17
[20] RAVIKOVITCH P, VISHNYAKOV A, NEIMARK A V. Density functional theories and molecular simulations of adsorption and phase transitions in nanopores[J]. Physical Review E, 2001, 64(1): 011602
[21] 刘希尧. 工业催化剂测试表征[M]. 北京: 中国石化出版社, 1990: 42-69.
[22] 白峰, 马鸿文. 13X沸石分子筛的比表面积和孔分布[J]. 现代地质, 2008, 5(22): 838-844
[23] ZHANG Z L, YANG Z H. Theoretical and practical discussion of measurement accuracy for physisorption with micro-and mesoporous materials[J]. Chinese Journal of Catalysis, 2013, 10: 1797-1810