Liquid−Liquid and Liquid−Liquid−Solid Equilibrium of the Poly(ethylene glycol) Dimethyl Ether 2000 + Sodium Sulfate + Water System

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• 作者：Mohammed Taghi Zafarani-Moattar ; Dariush Nikjoo
• 刊名：Journal of Chemical & Engineering Data
• 出版年：2008
• 出版时间：November 13, 2008
• 年：2008
• 卷：53
• 期：11
• 页码：2666-2670
• 全文大小：142K
• 年卷期：v.53,no.11(November 13, 2008)
• ISSN：1520-5134

文摘

The phase diagram for the poly(ethylene glycol) dimethyl ether (PEGDE) + Na₂SO₄ + H₂O system at 298.15 K using PEGDE with a molar mass of 2000 was determined. Compositions of the liquid−liquid and the liquid−liquid−solid equilibria were determined using calibration curves of refractive index of the solutions, and atomic absorption (AA) and X-ray diffraction analyses were made on the solids. The solid phase in equilibrium with the biphasic region was anhydrous Na₂SO₄. An empirical nonlinear three-parameter expression developed by Merchuk was used for reproducing the experimental binodal data at T = (288.15, 298.15, 308.15, and 318.15) K, and the fitting parameters were obtained for the corresponding temperatures. The effects of temperature on the binodal curve were also studied, and it was observed that the area of the biphasic region increased slightly with an increase in temperature. The experimental tie-line compositions at the aforementioned temperatures were fitted to both the Othmer−Tobias and Bancroft and Setschenow-type equations. Correlation coefficients for all equations are reported.