-
摘要: 以吸附式天然气（ANG）吸附剂的工程应用为目的，以0-10 MPa、283.15-303.15 K甲烷在层状石墨烯（GS（3D），比表面积2062 m2/g）和活性炭SAC-01（比表面积1507 m2/g）上的吸附平衡数据作分析。首先，在77.15 K下由氮气吸附表征样品的孔径大小及分布（PSD）和比表面积。其次，选择极低压力下的吸附平衡数据标定亨利定律常数，确定甲烷在两吸附剂上的极限吸附热，并由维里方程和10-4-3势能函数计算甲烷与两吸附剂壁面之间的相互作用势。最后，依据测试的甲烷在吸附剂上的高压吸附平衡数据，比较了Langmuir系列方程的关联数据后的拟合精度，并由绝对吸附量计算了甲烷的等量吸附热。结果表明，甲烷在GS（3D）和活性炭SAC-01上的平均极限吸附热为23.07、20.67 kJ/mol；283.15 K下甲烷分子与GS（3D）和活性炭SAC-01之间的交互作用势εsf/k为67.19、64.23 K，与洛伦混合法则的计算值64.60 K相近；Toth方程关联甲烷在活性炭SAC-01和GS（3D）上吸附平衡数据的拟合累计相对误差为0.25%和2.29%；甲烷在活性炭SAC-01和GS（3D）上的等量吸附热平均值为16.8和18.3 kJ/mol。相对于活性炭SAC-01，比表面积和微孔容积均较高的GS（3D）对甲烷的吸附更具有优势。Abstract: In order to develop a new kind of adsorbent for the storage of natural gas by adsorption, the activated carbon SAC-01 and the layered graphene GS(3D), which have a specific surface area about 2062 m2/g and 1507 m2/g, respectively, were comparatively studied as per adsorption equilibrium data measured at the temperature of 283.15-303.15 K and the pressure of 0-10 MPa. The pore size distribution (PSD) and BET specific surface area of the GS(3D) and the activated carbon were firstly determined by analyzing adsorption isotherms of nitrogen at 77.15 K through Horvath-Kawazoe equation calculation. The Henry law constant was used to calculate the limit isosteric heat of methane adsorption in correspondence with the low surface coverage, the interaction potentials between methane molecule and the surface of two adsorbents were then plotted by employing Virial equation and 10-4-3 potential function. The adsorption data, which were volumetrically measured under high pressures, were correlatively fitted by Langmuirian equations through nonlinear regression. Toth equation with the highest accuracy in predicting adsorption data was then used to calculate the absolute adsorption amount, which was finally employed to calculate the isosteric heat of adsorption via Clausius-Clapeyron equation. The result shows that the limit isosteric heat of methane adsorption on the GS(3D) and the activated carbon is about 23.07 and 20.67 kJ/mol, respectively, and the corresponding interaction potential εsf/k between methane molecule and the GS(3D) or the activated carbon is about 67.19 and 64.23 K at temperature 283.15 K, respectively, which are similar to 64.60 K determined by Lorenz-Berthelot mixing law. The accumulated relative error of the Toth equation for predicting the adsorption equilibrium of methane on the activated carbon and GS(3D) is 0.25% and 2.29%, respectively, and the mean isosteric heat of methane adsorption on the GS(3D) and the activated carbon is about 18.3 and 16.8 kJ/mol, respectively. It suggests that the GS (3D) with a larger specific surface area and micro-pore volume takes more advantages in methane adsorption in comparing with the activated carbon.
-
Key words:
- methane /
- graphene sheets /
- activated carbon /
- adsorption
-
图 1 77.15 K氮在试样上的吸附等温线(a)及试样的PSD谱图(b)
Figure 1 Isotherms (a) of nitrogen at 77.15 K on two samples and the PSD (b) of the adsorbents
图 2 低压下甲烷在SAC-01活性炭(a)和GS(3D)(b)上的吸附等温线
Figure 2 Isotherms of methane adsorption on activated carbon (a) and GS(3D) (b) at very low pressure ranges
图 3 甲烷在SAC-01(a)和GS(3D)(b)上的过剩吸附等温线
Figure 3 Isotherms of excess amounts of methane adsorption on activated carbon SAC-01 (a) and layered graphene GS(3D) (b)
图 4 293.15 K下关联拟合参数后的吸附模型计算甲烷在活性炭SAC-01(a)和层状石墨烯GS(3D)(b)上吸附量与测试值之间的相对误差
Figure 4 Relative errors between experimental data and those predicted by correlatively fitted adsorption models for methane adsorption on activated carbon (a) and layered graphene GS(3D) (b) at 293.15 K
图 5 甲烷在活性炭SAC-01(a)和层状石墨烯GS(3D)(b)上的绝对吸附等温线
Figure 5 Isotherms of absolute adsorption amounts of methane on activated carbon SAC-01 (a) and layered graphene GS(3D) (b)
图 6 甲烷在活性炭SAC-01和层状石墨烯GS(3D)上的等量吸附热
Figure 6 Isosteric heat of methane adsorption on activated carbon SAC-01 and layered graphene GS(3D)
表 1 SAC-01活性炭和GS(3D)的结构参数
Table 1 Structural parameters of activted carbon SAC-01 and layered graphene GS(3D)
Sample BET specific surface area
A/(m2·g-1)Pore width
d/nmMicro-pore volume
v/(mL·g-1)Packing density
ρ/(g·cm-3)SAC-01 1507 0.77 0.54 0.51 GS(3D) 2062 0.93 0.61 0.22 
下载: 导出CSV
表 2 低压下甲烷在两吸附剂上的标绘参数
Table 2 Parameters of methane adsorption on two adsorbents determined by adsorption data measured at low pressure
T/K HP/(mmol·Pa·g) BASE+9/(m3·g-1) qst0/(kJ·mol-1) SAC-01 GS(3D) SAC-01 GS(3D) SAC-01 GS(3D) 283.15 0.00179 0.00154 31.11 10.44 21.52 24.74 293.15 0.00142 0.00118 16.97 5.10 21.13 23.13 303.15 0.00103 0.00065 6.59 0.93 19.36 21.34 Mean value 0.00141 0.00112 18.22 5.49 20.67 23.07
下载: 导出CSV
表 3 293.15 K时甲烷在活性炭SAC-01上模型值的累计相对误差
Table 3 Accumulated relative errors from the results of methane adsorption on activated carbon SAC-01 at 293.15 K determined by different adsorption models
Adsorption model Accumulated relative errors ε/% 0-1 MPa 1-10 MPa 0-10 MPa Langmuir 24.74 7.12 15.93 Langmuir-Freundlich 1.75 0.26 1.01 Toth 0.25 0.24 0.25
下载: 导出CSV
表 4 293.15 K时甲烷在层状石墨烯GS(3D)上模型计算值的累计相对误差
Table 4 Accumulated relative errors from the results of methane adsorption on layered graphene at 293.15 K determined by different adsorption models
Adsorption model Accumulated relative errors ε/% 0-1 MPa 1-10 MPa 0-10 MPa Langmuir 5.58 1.37 3.48 Langmuir-Freundlich 4.98 0.80 2.89 Toth 3.90 0.69 2.29
下载: 导出CSV
表 5 甲烷分子与不同碳基材料壁面之间的相互作用势
Table 5 Interaction potentials between methane molecules and adsorbent surface of different carbon based materials
T/K εsf/k/K Eminza/10-20J SAC-01 GS(3D) SAC-01 GS(3D) 283.15 64.12 68.07 4.83 5.00 293.15 64.86 67.40 4.91 5.10 303.15 63.81 66.09 4.85 5.15
下载: 导出CSV
-
[1] YAN Y, KOLOKOLOV D I, SILVA I D, STEPANOV A G, BLAKE A J, DAILLY A, MANUEL P, TANG C C, YANG S H, SCHRÖDER M. Porous metal-organic polyhedral frameworks with optimal molecular dynamics and pore geometry for methane storage[J]. Am Chem Soc, 2017, 139:13349-13360. doi: 10.1021/jacs.7b05453 [2] WALKER N R, WISSINK M L, DEL V D A, REITZ R D. Natural gas for high load dual-fuel reactivity controlled compression ignition in heavy-duty engines[J]. J Energy Resour Technol Trans ASME, 2015, 137(4), Article number:042202. [3] EDUARDO F S A, FABIO B N, ARNALDO JR F. The main catalytic challenges in GTL(gas-to-liquids) processes[J]. Catal Sci Technol, 2011, 1(5):5698-713. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=9823f5c8a08852f5ec0dc5063168d971 [4] KUMAR K V, PREUSS K, TITIRICI M M, RODRǏGUEZ-REINOSO F. Nanoporous materials for the onboard storage of natural gas[J]. Chem Rev, 2017, 117(3):1796-1825. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=ea466680693db849047c47a7dd89d919 [5] BAGHERI N, ABEDI J. Adsorption of methane on corn cobs based activated carbon[J]. Chem Eng Res Des, 2011, 89(10):2038-2043. doi: 10.1016/j.cherd.2011.02.002 [6] BYAMBA-OCHIR N, WANG G S, BALATHANIGAIMANI M S, MOON H. High density Mongolian anthracite based porous carbon monoliths for methane storage by adsorption[J]. Appl Energy, 2017, 190:257-265. doi: 10.1016/j.apenergy.2016.12.124 [7] JIA Z, LI H, YU Z, WANG P, FAN X L. Densification of MOF-5 synthesized at ambient temperature for methane adsorption[J]. Mater Lett, 2011, 65(15):2445-2447. https://www.sciencedirect.com/science/article/abs/pii/S0167577X11004903 [8] MORRIS R E, WHEATLEY P S. Gas storage in nanoporous materials[J]. Angew Chem, 2008, 47(27):4966-4981. doi: 10.1002/anie.v47:27 [9] KIM S Y, KIM A R, YOON J W, KIM H J, BAE Y S. Creation of mesoporous defects in a microporous metal-organic framework by an acetic acid-fragmented linker co-assembly and its remarkable effects on methane uptake[J]. Chem Eng J, 2018, 335:94-100. doi: 10.1016/j.cej.2017.10.078 [10] SHAYEGANFAR F, NEEK-AMAL M. Methane molecule over the defected and rippled graphene sheet[J]. Solid State Commun, 2012, 152(15):1493-1496. doi: 10.1016/j.ssc.2012.04.049 [11] YANG D G, YANG N, NI J M, JING X, JIANG J K, LIANG Q H, REN T L, CHEN X P. First-principles approach to design and evaluation of graphene as methane sensors[J]. Mater Des, 2017, 119:397-405. doi: 10.1016/j.matdes.2017.01.087 [12] JIANG H, CHEN X L. Simulations on methane uptake in tunable pillared porous graphene hybrid architectures[J]. J Mol Graphics Modell, 2018, 85:223-231. doi: 10.1016/j.jmgm.2018.09.006 [13] BYAMBA-OCHIR N, WANG G S, BALATHANIGAIMANI M S, MOON H. High density Mongolian anthracite based porous carbon monoliths for methane storage by adsorption[J]. Appl Energy, 2017, 190:257-265. doi: 10.1016/j.apenergy.2016.12.124 [14] BAGHERI N, ABEDI J. Adsorption of methane on corn cobs based activated carbon[J]. Chem Eng Res Des, 2011, 89:2038-2043. doi: 10.1016/j.cherd.2011.02.002 [15] 郑青榕, DO Duong D.甲烷在石墨化热解碳黑和活性炭上的吸附[J].燃料化学学报, 2010, 38(3):359-364. doi: 10.3969/j.issn.0253-2409.2010.03.018ZHENG Qing-rong, DO Duong D. Methane adsorption on activated carbon and carbon black[J]. J Fuel Chem Technol, 2010, 38(3):359-364. doi: 10.3969/j.issn.0253-2409.2010.03.018 [16] 郑青榕, 朱子文, 罗婉珍.吸附式天然气储罐充放气过程的试验研究[J].石油与天然气化工, 2014, 43(5):497-500. doi: 10.3969/j.issn.1007-3426.2014.05.007ZHENG Qing-rong, ZHU Zi-wen, LUO Wan-zhen. Experimental study of the ANG storage tank during charge and discharge[J]. Chem Eng Oil Gas, 2014, 43(5):497-500. doi: 10.3969/j.issn.1007-3426.2014.05.007 [17] 周子娥, 薛春瑜, 阳庆元, 仲崇立.新型储甲烷金属-有机骨架材料的设计[J].化学学报, 2009, 67(6):477-482. doi: 10.3321/j.issn:0567-7351.2009.06.004ZHOU Zi-e, XUE Chun-yu, YANG Qing-yuan, ZHONG Chong-li. Design of metal-organic frameworks for methane storage[J]. Acta Chim Sin, 2009, 67(6):477-482. doi: 10.3321/j.issn:0567-7351.2009.06.004 [18] 曾余瑶, 张秉坚.金属-有机骨架材料MOF-5的改进与吸附甲烷的巨正则蒙特卡罗模拟[J].物理化学学报, 2008, 24(8):1493-1497. doi: 10.3866/PKU.WHXB20080828ZENG Yu-yao, ZHANG Bing-jian. Designed metal-organic frameworks based on MOF-5 and their methane adsorption calculation by grand canonical monte carlo method[J]. Actq Phys-Chim Sin, 2008, 24(8):1493-1497. doi: 10.3866/PKU.WHXB20080828 [19] TAHMOORESI M, SABZI F. Sorption of methane in a series of Zn-based MOFs studied by PHSC equation of state[J]. Fluid Phase Equilib, 2014, 381(381):83-89. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=63d767eb9fae210c02fdd01b1524642e [20] 张伊, 顾奕奕, 陈云琳, 王铭扬, 张兴华.掺杂金属离子对MOF-5吸附甲烷分子的影响[J].化工新型材料, 2015, 43(2):93-96. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=hgxxcl201502031ZHANG Yi, GU Yi-yi, CHEN Yun-lin, WANG Ming-yang, ZHANG Xing-hua. Influence of metal ions doping on the gas-adsorption property of MOF-5[J]. New Chem Mater, 2015, 43(2):93-96. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=hgxxcl201502031 [21] XU G J, MENG Z S, LIU Y Z, GUO X J, DENG K M, LU R F. Heterofullerene-linked metaleorganic framework with lithium decoration for storing hydrogen and methane gases[J]. Int J Hydrogen Energy, 2019, 44(13):6702-6708. doi: 10.1016/j.ijhydene.2019.01.134 [22] 王晓华, 郑青榕, 高帅.甲烷在石墨烯与活性炭上的吸附平衡[J].集美大学学报(自然版), 2013, 18(6):451-455. http://d.old.wanfangdata.com.cn/Periodical/jmdxxb-zr201306009WANG Xiao-hua, ZHENG Qing-rong, GAO Shuai. Adsorption equilibrium of methane on graphene sheets and activated carbon[J]. J Jimei Univ, Nat Sci, 2013, 18(6):451-455. http://d.old.wanfangdata.com.cn/Periodical/jmdxxb-zr201306009 [23] 王泽浩, 郑青榕, 朱子文, 唐政.甲烷在碳基材料和MOFs上极低压力下的吸附平衡[J].天然气化工-C1化学与化工, 2018, 43(5):15-20. http://d.old.wanfangdata.com.cn/Periodical/trqhg201805004WANG Ze-hao, ZHENG Qing-rong, ZHU Zi-wen, TANG Zhen. Adsorption equilibrium of methane on carbon-based material and MOFs at very low pressure[J]. Nat Gas Chem Ind, 2018, 43(5):15-20. http://d.old.wanfangdata.com.cn/Periodical/trqhg201805004 [24] ZHENG Q R, JI X, GAO S, WANG X. Analysis of adsorption equilibrium of hydrogen on graphene sheets[J]. Int J Hydrogen Energy, 2013, 38(25):10896-10902. doi: 10.1016/j.ijhydene.2013.01.098 [25] CLARK A. The Theory of Adsorption and Catalysis[M]. New York:Academic Press, 1970:160-271. [26] MEEKS O R, RYBOLT T R. Correlations of adsorption energies with physical and structural properties of adsorbate molecules[J]. J Colloid Interface Sci, 1997, 196(1):103-109. doi: 10.1006/jcis.1997.5198 [27] MENON P G. Adsorption at high pressures[J]. Chem Rev, 1968, 68(3):277-294. http://d.old.wanfangdata.com.cn/Periodical/cuihuaxb201312005 [28] ZHOU L, ZHOU Y P, LI M, CHEN P, WANG Y. Experimental and modeling study of the adsorption of supercritical methane on a high surface activated carbon[J]. Langmuir, 2000, 16(14):5955-5959. doi: 10.1021/la991159w [29] DO D D, H D D, TRAN K N. Analysis of adsorption of gases and vapors on nonporous graphitized thermal carbon black[J]. Langmuir, 2003, 19(14):5656-5668. doi: 10.1021/la020191e [30] STEELE W A. The Interaction of Gases with Solid Surface[M]. Oxford:Pergamon, 1974. [31] 曹达鹏, 高广图, 汪文川.巨正则系综Monte Carlo方法模拟甲烷在活性炭孔中的吸附存储[J].化工学报, 2000, 51(1):24-29. http://d.old.wanfangdata.com.cn/Periodical/hgxb200001005CAO Da-peng, GAO Guang-tu, WANG Wen-chuan. Grand canonical ensemble monte carlo simulation of adsorption storage of methane in slit micropores[J]. CIESC J, 2000, 51(1):24-29. http://d.old.wanfangdata.com.cn/Periodical/hgxb200001005 [32] BÉNARD P, CHAHINE R. Determination of the adsorption isotherms of hydrogenon activated carbons above the critical temperature ofthe adsorbate over wide temperature and pressureranges[J]. Langmuir, 2001, 17(6):1950-1955. doi: 10.1021/la001381x [33] ZHU Z W, ZHENG Q R, WANG Z H, TANG Z, CHEN W. Hydrogen adsorption on graphene sheets and nonporous graphitized thermal carbon black at low surface coverage[J]. Int J Hydrogen Energy, 2017, 42:18465-18472. doi: 10.1016/j.ijhydene.2017.04.173 -
点击查看大图
计量
- 文章访问数: 111
- HTML全文浏览量: 73
- PDF下载量: 15
- 被引次数: 0
