Ponraj Yadava Krishnan, Borah Bhaskarjyoti
P. D. Patel Institute of Applied Sciences, Charotar University of Science and Technology, Changa, Anand, Gujarat, 388421, India.
P. D. Patel Institute of Applied Sciences, Charotar University of Science and Technology, Changa, Anand, Gujarat, 388421, India.
J Mol Graph Model. 2020 Jun;97:107574. doi: 10.1016/j.jmgm.2020.107574. Epub 2020 Feb 20.
Pure methane is an alternative source of cleaner energy. Although, natural gas contains around 90% of methane, there are other heavier alkanes such as ethane and propane. Presence of these heavier hydrocarbons affects the reusability of an adsorbed natural gas system (ANG). Thus, separation of these higher alkanes from methane is important. In the present study, we employed molecular simulation techniques to assess the performance of MOF Cu-BTC for separation of methane from ethane and propane at 298 K and for a range of pressure. The assessment was carried out on the basis of variety of performance metrics suitable for adsorption based separation. The performance metrics that we relied upon are adsorption selectivity, working capacity, regenerability (R%), adsorption performance score (APS), diffusion selectivity, and membrane selectivity. We investigated the performance for two equimolar binary mixtures - methane/ethane and methane/propane, and two ternary mixtures - one equimolar mixture and the other containing 90% methane, 7% ethane, and 3% propane. The adsorption selectivity of ethane over methane and propane over methane are really attractive indicating good performance of the MOF in separating the two binary mixtures. We also investigated the effect of the presence of ethane and propane on the mobility of methane. The diffusivities of methane, although, reduces by some factor in presence of ethane and propane, are sufficiently higher at all the pressures and at different compositions with ethane and propane. Finally, we assessed the performance of Cu-BTC as a membrane for separation of methane from ethane and propane.
纯甲烷是一种更清洁能源的替代来源。虽然天然气中甲烷含量约为90%，但还含有其他较重的烷烃，如乙烷和丙烷。这些较重烃类的存在会影响吸附天然气系统（ANG）的可重复使用性。因此，将这些高级烷烃与甲烷分离很重要。在本研究中，我们采用分子模拟技术来评估MOF Cu - BTC在298 K和一系列压力下从乙烷和丙烷中分离甲烷的性能。该评估是基于适用于基于吸附分离的各种性能指标进行的。我们所依赖的性能指标有吸附选择性、工作容量、可再生性（R%）、吸附性能得分（APS）、扩散选择性和膜选择性。我们研究了两种等摩尔二元混合物——甲烷/乙烷和甲烷/丙烷，以及两种三元混合物——一种等摩尔混合物和另一种含有90%甲烷、7%乙烷和3%丙烷的混合物的性能。乙烷对甲烷以及丙烷对甲烷的吸附选择性非常有吸引力，表明MOF在分离这两种二元混合物方面性能良好。我们还研究了乙烷和丙烷的存在对甲烷迁移率的影响。甲烷的扩散率虽然在乙烷和丙烷存在时会降低一定程度，但在所有压力以及与乙烷和丙烷的不同组成下仍足够高。最后，我们评估了Cu - BTC作为从乙烷和丙烷中分离甲烷的膜的性能。
