1. Workshop CIP 1 2014 17-19 Mars 2014, Yasmine Hammamet
Based on the same experimental data of shear viscosities and densities of DMA + Met binary mixtures at four different temperatures from to K and at atmospheric pressure Based on the same experimental data of shear viscosities and densities of DMA + Met binary mixtures at four different temperatures from to K and at atmospheric pressure [1], some new theoretical approaches have been reported, for improving investigations of variation of Arrhenius activation energy and derived partial molar properties versus molar fraction composition. Arrhenius parameters of pure components (DMA and Met) as a function of temperature can be estimated. Correlation between the two Arrhenius parameters for binary mixtures permits us to reveal the viscosity Arrhenius temperature which characterizes the studied binary liquid mixture and can provide information on the vaporization temperature of the isobaric liquid vapor equilibrium. Also, this correlation can give evidence of the existence of distinct composition regions with different behaviours. Thus, supposing that the activation energy is a thermodynamic magnitude, we have determined the partial molar activation energy to release individual interaction’s contributions of each pure component within the mixture for each well-defined composition. Correlation between the molar quantities relative to the activation energies and the logarithm of the entropic factors of Arrhenius for DMA + Met mixtures over the temperature range can give a roughly linear behavior i.e. no observable change in curvature. This quasi-straight line behavior suggests us to make an empirical equation by introducing a new parameter TA denoted as viscosity Arrhenius temperature which characterizes each binary system. In the case of molar quantities, we consider that the Arrhenius temperature (TA) is no longer a constant over the whole range of composition, we introduce a new concept of the Arrhenius’ current temperature (TAi) for each pure component (i) to find its value at the two extreme positions i.e., at very high concentration and very high dilution respectively. The results derived in the studied binary system gives an interesting fact that the isobaric boiling point (Tbi) of the pure components is very close or strongly depends upon the viscosity Arrhenius’ current temperature (TAi). In conclusion, we can ascertain that with more mathematical handlings, we will be able to reveal some physical significances of the viscosity Arrhenius parameters and it definitely develops as well as improves the thermodynamic theories and also to predict some information on liquid-vapor diagram through the study of the viscosity versus temperature and molar fraction only in the liquid phase of binary mixture. We can add that an additional study on the eventual relationship between the Arrhenius temperature and the properties of great number binary mixtures can prove how the method predicts the properties of other non treated fluid mixtures. In order to tightly found the utility of the Arrhenius temperature and develop a means for estimating such quantities, more mixtures will be studied in future to give a more clear discussed protocol. To our knowledge, there is no stronger theoretical and physical basis of this study or any developed predictive methods for our initial assumptions and so we cannot able to provide more honestly our checking. We are very much hopeful that these original and interesting experimental findings can be well received by the theorists for developing new theoretical approaches. Also, in a future work, we will address the mutual correlation between the Arrhenius parameters and the effect of pressure on the viscosity and how correlation can be deduced with the theories already available.
Conclusion
Derived partial molar properties investigations of viscosity Arrhenius parameters in N,N-dimethylacetamide+methanol systems at different temperatures.
M. Dallel a,*, H. Salhi a, Z. Trabelsi a, E.S. Bel Hadj Hmida a, D. Das b, N. Ouerfelli a,c
Workshop CIP Mars 2014, Yasmine Hammamet
a Laboratoire de Biophysique et Technologies Médicales, Institut Supérieur des Technologies Médicales de Tunis, 9 Avenue Dr. Zouhaier Essafi 1006 Tunis,,:
b Department of Chemistry, Dinhata College, North Bengal University, Dinhata , Cooch-Behar, West Bengal, India;
c University of Dammam, Department of Chemistry, Girls College of Science, P.O. Box 838, Dammam 31113, Saudi Arabia.
Excess properties calculated from literature values of experimental density and viscosity in N,N-dimethylacetamide + methanol binary mixtures (from to ) K can lead us to test different correlation equations as well as their corresponding relative functions. Inspection of the Arrhenius activation energy Ea and the enthalpy of activation of viscous flow DH* shows very close values, here we can define partial molar activation energy Ea1 and Ea2 for N,N-dimethylacetamide and methanol respectively along with their individual contribution separately. Correlation between the two Arrhenius parameters of viscosity in all compositions shows existence of main distinct behaviors separated by particular mole fractions in N,N-dimethylacetamide. In addition, we add that correlation between Arrhenius parameters reveals interesting Arrhenius temperature which is closely related to the vaporization temperature in the liquid vapor equilibrium and the limiting corresponding partial molar properties can permit us to estimate the boiling points of the pure components.
Abstract
Viscosity at infinite temperature (h∞ or As) in mPa·s for {Met (1) and DMA (2)} mixtures versus the mole fraction x1 of Met in the temperature range ( to ) K..
Results
Variation of the experimental Herráez exponent P12,exp,T (x1) (Eq. 5) for {Met (1) and DMA (2)} mixtures against mole fraction x1 in Met at the temperatures, (●): K; (○): K; (▲): K ; (∆): K and variation of P21,exp,T (x2) (Eq. 8) for {Met (1) and DMA (2)} mixtures against mole fraction x2 in DMA at the temperatures, (■): K; (□): K; (♦): K ; (◊): K.
Arrhenius activation energy Ea and enthalpy of activation of viscous flow DH* for {Met (1) and DMA (2)} mixtures versus the mole fraction x1 of N,N-dimethylformamide in the temperature range ( to ) K. (●): Ea / kJ·mol-1; (○): DH* / kJ·mol-1.
Logarithm of the entropic factor of Arrhenius –R·ln(As) and entropy of activation of viscous flow DS* for {Met (1) and DMA (2)} mixtures versus the mole fraction x1 of N,N-dimethylacetamide in the temperature range ( to ) K. (●): –R·ln(As/Pa·s) / (J·K-1·mol-1) ; (○): DS* / kJ·mol-1.
Correlation between the Arrhenius activation energy Ea (kJ·mol-1) of viscosity and the logarithm of the entropic factor of Arrhenius – R·ln(As/Pa·s) / ( J·K-1·mol-1) for {Met (1) and DMA (2)} mixtures in the temperature range ( to ) K. (●): experimental data points; (––): non linear least square fit.
Arrhenius activation energy Ea /(kJ·mol-1) and partial molar activation energies of viscosity (Eqs. 5 and 6) Eai /(kJ·mol-1) for {Met (1) and DMA (2)} mixtures as a function of the mole fraction of Met (x1) over the temperature range ( to ) K. (○): Ea(x1) ; (●): Ea1(x1) and ; (▲): Ea2(x1) .
Correlation between the partial molar Arrhenius activation energies Ea1(x1) and Ea2(x1) for {Met (1) + DMA (2)} mixtures over the temperature range ( to ) K.
Correlation between the partial molar quantities relative to the activation energies Eai /(kJ·mol-1) and the logarithm of the entropic factors of Arrhenius –R·ln(Asi/Pa·s) /(J·K-1·mol-1) related to, curve a, (●): Met (i=1) and curve b, (○): DMA (i=2) in {Met (1) + DMA (2)} mixtures as a function of the mole fraction of Met (x1) over the temperature range ( to ) K.
Logarithm of shear viscosity ln(h) for the system of {Met (1) and DMA (2)} mixtures versus the reciprocal absolute temperature at some fixed mole fractions x1 in the range of temperature ( to K). (●): x1 = ; (○): x1 = ; (▲): x1 = ; (∆): x1 = ; (■): x1 = ; (□): x1 = ; (♦): x1 = ; (◊): x1 = ; (▼): x1 = and (): x1 =
Shear viscosity (h) for the system of {Met (1) and DMA (2)} mixtures versus the mole fraction x1 of Met at the temperatures: (●) and (○): K ; (▲) and (∆): K; (■) and (□): K ; (♦) and (◊): K. full symbols: literature data [1] and empty symbols: interpolated data.
Variation the Arrhenius activation energy Ea (kJ·mol-1) of viscosity and the logarithm of the entropic factor of Arrhenius – R·ln(As/Pa·s) / ( J·K-1·mol-1) for {Met (1) and DMA (2)} mixtures versus the mole fraction x1 of Met in the temperature range ( to ) K. (●): Ea / kJ·mol-1; (○): – R·ln(As/Pa·s) / ( J·K-1·mol-1).
Comparison between the current Arrhenius temperature (TAi) / K for (xi≈1) and the corresponding boiling temperature Tbi / K of the pure component (i) in some binary mixtures.
Component 1
Component 2
TA1 / K
Tb1 / K
TA2 / K
Tb2 / K
DMA
Met
418.7
438.15
319.4
337.85 FA
429.1
479.6
483.65
EOE
440.0
438.45
410.0
408.15
Water
456.1
378.5
373.15
Dioxane
378.6
374.25
380.5