A modification of the extended UNIQUAC model is proposed for the description of the non-ideality of protein solutions. Here, the Staverman–Guggenheim combinatorial contribution used in extended UNIQUAC model is replaced by the Flory–Huggins term to take into account the size differences between the protein and solvent. This new model allows an excellent description of the activity coefficients ...

The extended universal quasichemical (UNIQUAC) model is a thermodynamic model for solutions containing electrolytes and nonelectrolytes. The model is a Gibbs excess function consisting of a Debye–Hückel term and a standard UNIQUAC term. The model only requires binary ion-specific interaction parameters. A unique choice of standard states makes the model able to reproduce solid–liquid, vapor–liq...

In this study, the Langmuir adsorption isotherm has been coupled with activity coefficient models for prediction of surface tension of single and mixed electrolyte solutions. Various activity models such as Meissner, Pitzer and extended UNIQUAC have been used and coupled with Langmuir adsorption isotherm. The model parameters were determined through mathematical optimization using experimental ...

The effect of the partition coefficient on simulation operation a biotrickling filter treating mixture sulfur compounds was analyzed to evaluate pertinence using Henry’s law in determining its removal capacity. analysis consisted that bio-oxides hydrogen sulfide (H2S), dimethyl (DMS), methyl mercaptan (MM) and disulfide (DMDS) different types models for coefficient: pure water, adjusted from ex...

Vapor-liquid equilibrium in NH3-CO2-H2O system at high pressures has been studied. The UNIQUAC-NRF model for this system was extended by using the Goppert 4 maurer reported datas. Since the system contains molecules and ionic species the binary interaction parameters considered, where those are of molecule-molecule, molecule-ion and ion-ion types. These interaction parameters are taken as c...

vapor-liquid equilibrium in nh3-co2-h2o system at high pressures has been studied. the uniquac-nrf model for this system was extended by using the goppert 4 maurer reported datas. since the system contains molecules and ionic species the binary interaction parameters considered, where those are of molecule-molecule, molecule-ion and ion-ion types. these interaction parameters are taken as const...

10 A new UNIQUAC based predictive local composition model is here compared against predictive Wilson and predictive modified UNIQUAC on their abilities to predict wax formation. For that purpose a very large database of phase equilibrium data of both synthetic and real hydrocarbon fluids, at both low and high pressures, will be used. It is shown that the new UNIQUAC model does not suffer from t...

In this study liquid phase equilibrium compositions were measured at 298.15 K under atmospheric pressure for (water + propan-1-ol + diethyl carbonate (DEC) + benzene or cyclohexane or heptane) quaternary systems and (water + DEC + propan-1-ol or benzene or cyclohexane) ternary systems. Good correlation of the experimental LLE data was seen for the measured systems by both modified and extended ...