| Abstract
| - Adsorption of binary hydrocarbon mixtures involving methane in carbon slit pores is theoretically studiedhere from the viewpoints of separation and of the effect of impurities on methane storage. It is seen thateven small amounts of ethane, propane, or butane can significantly reduce the methane capacity of carbons.Optimal pore sizes and pressures, depending on impurity concentration, are noted in the present work,suggesting that careful adsorbent and process design can lead to enhanced separation. These results areconsistent with earlier literature studies for the infinite dilution limit. For methane storage applicationsa carbon micropore width of 11.4 Å (based on distance between centers of carbon atoms on opposing walls)is found to be the most suitable from the point of view of lower impurity uptake during high-pressureadsorption and greater impurity retention during low-pressure delivery. The results also theoreticallyconfirm unusual recently reported observations of enhanced methane adsorption in the presence of a smallamount of heavier hydrocarbon impurity.
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