Adsorption and separation of binary and ternary mixtures of SO2, CO2 and N2 by ordered carbon nanotube arrays: grand-canonical Monte Carlo simulations.
Adsorption and separation of binary and ternary mixtures of SO2, CO2 and N2 by ordered carbon nanotube arrays: grand-canonical Monte Carlo simulations.
复制标题
DOI：
10.1039/c5cp06377a
复制
发表时间：
2016-01
期刊：
影响因子：
--
通讯作者：
M. Rahimi;J. Singh;F. Müller-Plathe
中科院分区：
文献类型：
--
作者：
M. Rahimi;J. Singh;F. Müller-Plathe
采用巨正则蒙特卡罗（GCMC）方法和理想吸附溶液理论研究了SO2-CO2、SO2-N2和CO2-N2二元混合物在定向双壁碳纳米管束中的吸附分离行为.在303 K下进行了模拟与3 nm的内径和各种管间距离的纳米管。结果表明，管间距d = 0的填料对SO2-N2和CO2-N2的选择性最高。对于SO2-CO2的情况，具有最大选择性的最佳管间距离取决于所施加的压力，使得在p < 0.8巴时d = 0显示最高选择性，并且在0.8巴< p < 2.5巴时，最高选择性属于d = 0.5nm。理想吸附溶液理论不能预测含SO2二元体系的吸附，特别是当d = 0时。随着管间距离的增加，基于理想吸附溶液理论的预测变得更接近GCMC模拟。只有在CO2-N2的情况下，理想吸附溶液理论是处处符合模拟。在所有三种气体的三元混合物中，由于N2分子与CNT之间的弱相互作用，SO2和CO2的行为与SO2-CO2二元混合物中的行为相似。
The adsorption and separation behavior of SO2-CO2, SO2-N2 and CO2-N2 binary mixtures in bundles of aligned double-walled carbon nanotubes is investigated using the grand-canonical Monte Carlo (GCMC) method and ideal adsorbed solution theory. Simulations were performed at 303 K with nanotubes of 3 nm inner diameter and various intertube distances. The results showed that the packing with an intertube distance d = 0 has the highest selectivity for SO2-N2 and CO2-N2 binary mixtures. For the SO2-CO2 case, the optimum intertube distance for having the maximum selectivity depends on the applied pressure, so that at p < 0.8 bar d = 0 shows the highest selectivity and at 0.8 bar < p < 2.5 bar, the highest selectivity belongs to d = 0.5 nm. Ideal adsorbed solution theory cannot predict the adsorption of the binary systems containing SO2, especially when d = 0. As the intertube distance is increased, the ideal adsorbed solution theory based predictions become closer to those of GCMC simulations. Only in the case of CO2-N2, ideal adsorbed solution theory is everywhere in good agreement with simulations. In a ternary mixture of all three gases, the behavior of SO2 and CO2 remains similar to that in a SO2-CO2 binary mixture because of the weak interaction between N2 molecules and CNTs.