Apparent molar volumes, apparent isentropic compressibilities, and viscosity B-coefficients of 1-ethyl-3-methylimidazolium bromide in aqueous di-potassium hydrogen phosphate and potassium di-hydrogen phosphate solutions at T = (298.15, 303.15, 308.15, 313.15, and 318.15) K

作者：Zafarani Moattar Mohammed Taghi^*; Sarmad Shokat

来源：Journal of Chemical Thermodynamics, 2012, 54: 192-203.

DOI：10.1016/j.jct.2012.03.032

• Ionic liquids
• Apparent molar volume
• Isentropic compressibility
• Viscosity B-coefficient
• Interaction parameters

Apparent molar volumes V-phi, apparent isentropic compressibilities k(phi), and viscosity B-coefficients for 1-ethyl-3-methylimidazolium bromide (EmimBr) in aqueous di-potassium hydrogen phosphate (K2HPO4) solutions with salt weight fractions (w(s) = 0.00, 0.10, 0.15, and 0.20) and potassium di-hydrogen phosphate (KH2PO4) solutions with salt weight fractions (w(s) = 0.00, 0.04, 0.07, and 0.10) have been determined from solution density, sound velocity and viscosity measurements at temperatures over the range (298.15 to 318.15) K as function of concentration of 1-ethyl-3-methylimidazolium bromide (EmimBr). In the investigated temperature range, the relation: V-phi(0) - a(0) + a(1)T + a(2)T(2); has been used to describe the temperature dependence of the standard partial molar volumes V-phi(0). These results have, in conjunction with the results obtained in pure water, been used to deduce the standard volumes of transfer Delta V-phi(0) and viscosity B-coefficients of transfer for 1-ethyl-3-methylimidazolium bromide from water to aqueous K2HPO4 and KH2PO4 solutions for rationalizing various interactions in the ternary solutions. The structure making or breaking ability of 1-ethyl-3-methylimidazolium bromide has been discussed in terms of the sign of (partial derivative V-2(phi)0/partial derivative T-2). An increase in the transfer volume of 1-ethyl-3-methylimidazolium bromide with increasing phosphate salts concentration has been explained by Friedman-Krishnan co-sphere model. The activation parameters of viscous flow for the ternary solutions investigated were also determined and discussed by the application of transition state theory.

• 出版日期2012-11