期刊
JOURNAL OF CHEMICAL THERMODYNAMICS
卷 42, 期 1, 页码 8-16出版社
ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD
DOI: 10.1016/j.jct.2009.06.025
关键词
CO2 hydrate; Tetrahydrofuran; Hydrate phase behaviour; Pseudo-retrograde behaviour
资金
- Institute Technology PETRONAS (ltd), Malaysia
In the present work, the three- and four-phase hydrate equilibria of (carbon dioxide (CO2) + tetrahydrofuran (THF) + water) system are measured by using Cailletet equipment in the temperature and pressure range of (272 to 292) K and (1.0 to 7.5) MPa, respectively, at different CO2 concentration. Throughout the study, the concentration of THF is kept constant at 5 mol% in the aqueous solution. In addition, the fluid phase transitions of L-w-L-v-V -> L-w-L-v (bubble point) and L-w-L-v-V -> L-w-V (dew point) are determined when they are present in the ternary system. For comparison, the three-phase hydrate equilibria of binary ( CO2 + H2O) are also measured. Experimental measurements show that the addition of THF as a hydrate promoter extends hydrate stability region by elevating the hydrate equilibrium temperature at a specified pressure. The three-phase equilibrium line H-L-w-V is found to be independent of the overall concentration of CO2. Contradictory, at higher pressure, the phase equilibria of the systems are significantly influenced by the overall concentration of CO2 in the systems. A liquid-liquid phase split is observed at overall concentration of CO2 as low as 3 mol% at elevated pressure. The region is bounded by the bubble-points line (L-w-L-v-V -> L-w-L-v), dew points line (L-w-L-v-V -> L-w + V) and the four-phase equilibrium line (H + L-w + L-v + V). At higher overall concentration of CO2 in the ternary system, experimental measurements show that pseudo-retrograde behaviour exists at pressure between (2.5 and 5) MPa at temperature of 290.8 K. (C) 2009 Published by Elsevier Ltd.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据