Solubility and diffusivity of 1,1,1,2-tetrafluoroethane in room-temperature ionic liquids
Solubility and diffusivity of 1,1,1,2-tetrafluoroethane in room-temperature ionic liquids
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DOI：
10.1016/j.fluid.2006.01.026
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发表时间：
2006-04-25
影响因子：
2.6
通讯作者：
Yokozeki, A
中科院分区：
文献类型：
--
作者：
Shiflett, MB;Harmer, MA;Yokozeki, A
研究了1，1，1.2-正丁烷（R-134a）在7种室温离子液体（RTIL）中的溶解度和扩散系数。其中，五个RTIL是首次用三种新的氟磺酸根阴离子制备的，两个是可商购的（先前用R-134a研究了1-丁基-3-甲基咪唑六氟磷酸盐）。使用重量微量天平进行气体吸收测量。四个等温线（283.15，298.15，323.15，和348.15 K）在0.01至0.35 MPa的压力下测量。两种新合成的离子液体，十四烷基（三己基）磷1，1，2-三氟-2-（全氟乙氧基）乙磺酸盐和三丁基（十四烷基）磷1，1，2，3，3，3-六氟丙磺酸盐与R-134a具有最强的相互作用（拉乌尔定律的负偏差）。实验气体溶解度数据成功地与非随机双液（NRTL）溶液模型。使用时间依赖性吸收数据计算扩散率，使用基于修改的斯托克斯-爱因斯坦方程的模型分析扩散率。R-134a的衍生分子尺寸比已知尺寸大2 - 3倍。所观察到的扩散系数的量值为10（-10）至10（-11）m（2）s（-1），这比在各种有机液体中发现的典型值低约10 - 100倍。(c)2006 Elsevier B.V.保留所有权利。
The solubility and diffusivity of 1,1,1.2-tetrafluoroethane (R-134a) in seven room-temperature ionic liquids (RTILs) are presented. Among them, five of the RTILs were prepared for the first time with three new fluorocarbon sulfonate anions, and two were commercially available (1-butyl-3-methylimidazolium hexafluorophosphate was previously studied with R-134a). The gas absorption measurements were made using a gravimetric microbalance. Four isotherms (283.15, 298.15, 323.15, and 348.15 K) were measured at pressures from 0.01 to 0.35 MPa. Two of the newly synthesized ionic liquids, tetradecyl(trihexyl)phosphonium 1,1,2-trifluoro-2-(perfluoroethoxy)ethanesulfonate and tributyl(tetradecyl)phosphonium 1,1,2,3,3,3-hexafluoropropanesulfonate had the strongest interaction (negative deviations from Raoult's Law) with R-134a. Experimental gas solubility data were successfully correlated with the nonrandom two-liquid (NRTL) solution model. The time-dependent absorption data was used to calculate diffusivities that were analyzed using a model based on a modified Stokes-Einstein equation. The derived molecular size for R-134a is 2-3 times larger than the known size. Magnitudes in the observed diffusion coefficients are 10(-10) to 10(-11) m(2) s(-1), which are about 10-100 times lower than typical values, found in various organic liquids. (c) 2006 Elsevier B.V. All rights reserved.