| Summary: | 碩士 === 中原大學 === 化學工程研究所 === 97 === This study presents the measurement of the diffusion coefficients of glycols in water at infinite dilution and the mutual diffusion coefficients of six aqueous glycols systems namely: ethylene glycol (EG), diethylene glycol (DEG), triethylene glycol (TEG), tetraethylene glycol (T4EG), propylene glycol (PG), dipropylene glycol (DPG). The diffusion coefficients had been measured using on the Taylor dispersion method. Experimental works were performed at atmospheric pressure, with temperature range of 30 to 50°C, and concentration range of 0 to 80 mol % (x1 = 0.2 ~ 0.8). Experimental validation using the binary system of EG and water showed that the experimental setup provides accurate mutual diffusion coefficient data. The diffusion coefficients of glycols in water at infinite dilution are found to varied systematically with the molar mass of the glycols. The obtained mutual diffusion coefficients were correlated by using a simple relation of Snijder et al. (1993) equation, UNIDIF equation (Hsu and Chen, 1998) and modified Darken equations(Li t al. 2001). The rough hard sphere theory (Dymond, 1974) also successfully describes the experimental mutual diffusivities in this study.
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