三成份交互擴散係數量測研究乙二醇 + 水 + 鹽類(氯化鋰或溴化鋰)系統

Ternary Mutual Diffusion Coefficients of Glycol + H2O + (LiCl or LiBr) Systems

彭紹維(Shao-Wei Peng)

指導教授 ： 李夢輝

中原大學/工學院/化學工程研究所/碩士(2010年)

https://doi.org/10.6840/cycu201000631

摘要

摘要
本研究以泰勒分散法(Taylor dispersion method)來量測glycol + salt + H2O系統於一大氣壓下之三成份交互擴散係數。本研究系統分為diethylene glycol (DEG) + lithium chloride (LiCl) + H2O與diethylene glycol (DEG) + lithium bromide (LiBr) + H2O；量測溫度為303.2 K、308.2 K、313.2 K，總溶質濃度為10 wt%、15 wt%、20 wt%；本研究中量測DEG + (LiCl or LiBr) + H2O之三成份交互擴散係數，因三成份系統的兩端點，為雙成份系統，因此另量測DEG + H2O與(LiCl or LiBr) + H2O之雙成份交互擴散係數。由實驗結果可知，主擴散係數(Dii與Djj)與溫度成正比關係，與總溶質濃度成反比關係；交叉擴散係數(Dij與Dji)與溫度成正比關係，與鹽類濃度亦成正比關係。本研究使用一經驗式modified Batchelor equation來代表主擴散係數(main diffusion coefficient)與交叉擴散係數(cross-diffusion coefficient)在不同濃度不同溫度下的關係，並可得到令人滿意的結果。實驗量測之三成份交互擴散係數可提供設計除溼設備－吸收塔之基礎數據。

關鍵字

無

並列摘要

Abstract
The ternary diffusion coefficients of diethylene glycol (DEG) + lithium chloride (LiCl) + water and diethylene glycol (DEG) + lithium bromide (LiBr) + water were measured for temperatures 30, 35 and 40oC using the Taylor dispersion technique. The ternary diffusion coefficients were reported for solutions containing a total solute (glycol + salt) concentration of 10, 15, 20 wt% for glycol-salt ratios (0.25, 0.5 and 0.75). The corresponding mutual diffusion coefficients of aqueous glycol and aqueous salt solutions were also measured. Results showed that the main diffusion coefficients increased with temperature and decreased with total solute concentration while the cross-diffusion coefficients increased with increasing temperature and salt concentration. An empirical equation was used to predict the values of the main and cross-diffusion coefficients as functions of temperature and solute concentration. The developed correlation yield satisfactory results.

並列關鍵字

無

參考文獻

葉桂賓，乙二醇(EG, DEG, TEG, T4EG, PG, DPG)水溶液及鹽類(LiCl或LiBr) + (DEG或TEG)水溶液之密度及黏度量測研究，中原大學化工所，2006年。

蔡志源，混合溶劑除溼劑之熱物性質密度、黏度及蒸氣壓量測，中原大學化工所，2004年。

Ahmed, C. S. K., Gandhidasan, P. and Al-Farayedhi, A. A. Simulation of a Hybrid Liquid Desiccant based Air-Conditioning System. Applied Thermal Engineering 1997, 17, 125-134.

Alizadeh, A., Nieto de Castro, C. A. and Wakeham, W. A. The theory of the Taylor Dispersion Technique for Liquid Diffusivity Measurements. Int. J. Thermophysics. 1980, 1, 243-284.

Aris, R. On the Dispersion of a Solute in a Fluid Flowing Through a Tube. Proc. R. Soc. London. 1956, A235, 67-77.