甲烷、乙烷、丙烷和丁烷在中孔活性炭上的吸附平衡

摘要

以活性炭AC1为吸附剂,在体积法实验装置上分别测定了其对甲烷、乙烷、丙烷和丁烷4种气体的吸附等温线,吸附温度分别为283、293、303和313 K。利用77 K吸附氮气数据表征AC1,得到其比表面积为956 m²·g^-1,孔体积为1.36 mL·g^-1,孔径分布在1~5 nm,中孔的比例达到了61%。AC1对4种气体的吸附等温线均为I型等温线,分别采用Langmuir方程和Langmuir-Freundlich方程(简称L-F方程)对吸附平衡数据进行拟合,结果表明,L-F方程具有更好的拟合效果,为后序的多组分吸附平衡研究提供了基础数据。AC1对乙烷/丙烷的吸附平衡选择性系数在1.7~2.5,吸附选择性随吸附压力的增大而减小,吸附温度对吸附选择性无明显影响。

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	苏伟
	吴菲菲
	孙艳

关键词：天然气；吸附分离；吸附等温线

Abstract：

The adsorption isotherms of methane, ethane, propane and butane were measured by a volumetric method on activated carbon AC1 at 283, 293, 303 and 313 K. Adsorption characteristic of AC1 was determined by nitrogen adsorption at 77 K. The BET surface area and pore volume calculated from the isotherm are 956 m²·g^-1 and 1.36 mL·g^-1, respectively. The pore size mainly distributes from 1 nm to 5 nm and the rate of mesopores is about 61%. Langmuir equation and Langmuir-Freundlich equation (L-F equation) were applied to fit the adsorption isotherms of methane, ethane, propane and butane. It is showed that all the isotherms are type I isotherms, and L-F equation is better than Langmuir equation to describe the isotherms, which provide fundamental data for the further research on multi-component adsorption equilibrium. The equilibrium adsorption selectivity coefficient of ethane/propane on AC1 is approximately 1.7-2.5. The adsorption selectivity is decreased under a higher adsorption pressure, while adsorption temperature has no significant effect on its selectivity.

Keywords： natural gas； adsorption separation； adsorption isotherm

Received 2014-04-05;

Fund:

国家自然科学基金项目(21206108)。

Corresponding Authors: 孙艳,E-mail:sunyan2011@tju.edu.cn。 Email: sunyan2011@tju.edu.cn

About author: 苏伟(1974-),男,副研究员,主要从事吸附材料与吸附分离方面的研究。

引用本文:

苏伟, 吴菲菲, 孙艳.甲烷、乙烷、丙烷和丁烷在中孔活性炭上的吸附平衡[J]. 化学工业与工程, 2016,33(3): 50-54

Su Wei, Wu Feifei, Sun Yan.Adsorption of Methane, Ethane, Propane and Butane on a Mesoporous Activated Carbon[J]. Chemcial Industry and Engineering, 2016,33(3): 50-54

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