Effect of temperature on the aggregation behaviour and thermodynamic properties of surface active ionic liquid 1-decyl-3-methylimidazolium bromide in aqueous solutions: Surface tension, vapour pressure osmometery, conductivity, volumetric and compressibility study
| Autor: | Rahmat Sadeghi, Omid Naderi |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
Chemistry
Vapor pressure Thermodynamics of micellization Analytical chemistry Molar conductivity Partial molar property 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Atomic and Molecular Physics and Optics 0104 chemical sciences Surface tension symbols.namesake Gibbs isotherm Critical micelle concentration symbols Organic chemistry General Materials Science Osmotic coefficient Physical and Theoretical Chemistry 0210 nano-technology |
| Zdroj: | The Journal of Chemical Thermodynamics. 102:68-78 |
| ISSN: | 0021-9614 |
| Popis: | The self-aggregation behaviour and thermodynamic properties of surface active ionic liquid (SAIL) 1-decyl-3-methylimidazolium bromide ([C10mim][Br]) in aqueous solution have been investigated by means of surface tension, vapour pressure osmometery, electrical conductivity, volumetric and compressibility measurements at different temperatures. The critical micelle concentrations (cmc) obtained from the different thermodynamic properties investigated show that the curves of cmc against temperature show a shallow minimum at about 298 K and an increasing trend at the higher temperature range. From the electrical conductivity measurements, the values of the degree of ionization of the counter ion on the micelles (α), thermodynamic properties of micellization ( Δ G m ∘ , Δ H m ∘ , Δ S m ∘ ) and infinite dilution molar conductivity ( Λ m ∘ ) for the SAIL investigated at different temperatures were obtained. The temperature dependency of infinite dilution partial molar properties ( V m ∘ and K m ∘ ), apparent molar properties at the critical micelle concentration ( V ϕ , cmc and K ϕ , cmc ), apparent molar properties in the micelle phase ( V ϕ mic and K ϕ mic ) and the change of apparent molar properties upon micellization ( Δ V ϕ , m and Δ K ϕ , m ) were derived from the experimental volumetric and compressibility values. The surface tension measurements provided a series of parameters, including surface tension at the cmc ( γ cmc ), adsorption efficiency (pC20), effectiveness of surface tension reduction ( Π cmc ), maximum surface excess concentration ( Γ max ) and minimum surface area per molecule (Amin) at interface of air/solution for the investigated SAIL at different temperatures. Finally, the osmotic properties of the binary mixture of [C10mim][Br] and water including the water activity, osmotic coefficient and vapour pressure were studied by using the vapour pressure osmometry. |
| Databáze: | OpenAIRE |
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