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...

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...

Solid-liquid equilibria for binary mixtures of {Methyl palmitate (1) + Naphthalene (2)} were measured using differential scanning calorimeter (DSC). Simple eutectic behaviours for this system are observed. The experimental results were correlated by means of the NRTL, Wilson, UNIQUAC and ideal models. The root-mean-square deviations of the solubility temperatures for all measured data vary from...

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 ...

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 ...

A predictive version of the UNIQUAC model is proposed for the description of the nonideality of paraffinic solid solutions. With this model, and using only pure component properties, is possible to adequately predict the phase behavior of complex hydrocarbon mixtures. Both liquid and solid phase compositions as well as the fraction of crystals in a partly frozen solution show a good agreement w...

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...

( ) A fundamental study was carried out to understand the aging or hardening of the wax-oil gels formed in the subsea pipelines during the flow of crude oil from offshore wells to shore. The aging process is a counterdiffusion phenomenon where there exists a ( ) critical carbon number CCN , and wax molecules with carbon numbers greater than the CCN diffuse into the gel matrices and ®ice ®ersa. ...

Prediksi Kesetimbangan Uap Cair Sistem Biner Aseton + Amil Alkohol pada Tekanan 101,3 kPa bertujuan untuk mengetahui kesetimbangan uap-cair sistem tersebut berdasarkan Hukum Raoult dan mengkorelasikan data dengan model Universal Quasi-Chemical (UNIQUAC). diawali menentukan fraksi mol campuran biner aseton amil alkohol menggunakan persamaan tekanan kPa. Kemudian, yang didapat dikorelasikan perhi...

Aiming at identify the shortcomings of the available models for the description of the solid phase non-ideality, new solid liquid equilibrium data for multicomponent hydrocarbon systems was measured. The Predictive UNIQUAC and Wilson models for the description of the solid p d s m ©