Adsorption and desorption characteristics of CF 4 , which is considered a significant global warming compound, were experimentally investigated. Dynamic behavior of feed gas mixture of CF 4 and N 2 was observed by breakthrough curve. Effects of CF 4 concentrations in the feed gas were investigated, and three pressurization methods were compared. Desorption experiments were carried out using vacuum blowdown and purge. Desorption curves with various N 2 flow rates, feed compositions, and purge time were obtained. The enrichment factor was high for low concentration of CF 4 . However, the time required for complete desorption was independent of CF 4 concentration. In the operation of separate vacuum blowdown and purge steps, a short period of vacuum blowdown followed by the purge step was effective.

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