Effect of the Alkyl Chain Length of the Cation on the Interactions between Water and Ammonium-Based Ionic Liquids: Experimental and COSMO-RS Studies

详细信息    查看全文

• 作者：Varadhi Govinda ; T. Vasantha ; Imran Khan ; Pannuru Venkatesu
• 刊名：Industrial & Engineering Chemistry Research
• 出版年：2015
• 出版时间：September 16, 2015
• 年：2015
• 卷：54
• 期：36
• 页码：9013-9026
• 全文大小：1134K
• ISSN：1520-5045

文摘

To improve the understanding of the molecular interactions of water with tetraalkyl ammonium-based ionic liquids (ILs) such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, and tetrabutylammonium hydroxide, thermophysical properties such as density (蟻), speed of sound (u), viscosity (畏) and refractive index (n_D) were measured and a computational study using COSMO-RS was performed. The derived properties such as excess volumes (V^E), deviation in isentropic compressibilities (螖魏_s), deviation in viscosities (螖畏), and deviation in refractive indices (螖n_D) under the same experimental conditions for these systems were also estimated. The observed V^E and 螖魏_s values are negative over the entire composition of ILs at all investigated temperatures, whereas 螖畏 and 螖n_D values are positive under the same experimental conditions. These results reveal that the ammonium-based ILs significantly affect the intermolecular interactions between the solvent molecules. The computational study allows a qualitative analysis of the results in terms of the ion鈥揹ipole interactions, ion-pair formation, and hydrogen bonding between ammonium-based ILs and water.