Modulation of capillary condensation by trace component

Impact of trace component on capillary condensation (CC) is investigated systematically using a classical density functional theory. It is discovered that (i) presence of the trace component makes the CC to occur at much lower condensation pressure than when its absence; (ii) Lennard-Jones potential parameters like size parameter and energy parameter of the trace component, and its concentration in the bulk adsorption system, show their effects the most remarkably within a particular range beyond which the effects eventually become insignificant. The present discoveries have implications in low pressure storage of gases, separation and enrichment of low concentration component, and easy control of CC transition, etc.