Experimental Study of Mass Transfer of Carbon Dioxide in Quiescent N-Decane

摘要

By experimental visual observation, the mass transfer of gaseous carbon dioxide into quiescent liquid n-decane was confirmed to occur predominantly by free convection. Subsequently, the rate of mass transfer of CO_2 in n-decane was studied as a function of the hydraulic radius of the liquid phase at a fixed temperature and pressure, using longitudinal glass rods packing to vary the hydraulic radius. By introducing the concept of "effective" diffusivity, the system was analyzed as a transient, one-dimensional, semi-infinite mass transfer. The experimental results indicate the rate of mass transfer to be strongly dependent on the hydraulic radius as well as the void fraction of the packing. The effective diffusivity obtained is orders of magnitude larger than a typical liquid phase Fickian diffusivity. The reproducibility of the effective diffusivity depended strongly on reproducing the configuration of the cross-section of the liquid. The tortuosity of the mass transfer path, which was introduced using glass beads, did not significantly retard the mass transfer process.