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Showing 1 to 20 of 21 for “"UNIFAC"”.
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Experimentelle und theoretische Untersuchungen zur Erweiterung der Gruppenbeitragsmethoden UNIFAC und Modified UNIFAC (Dortmund)
… mit der Untersuchung der Gruppenbeitragsmethoden UNIFAC und Modified UNIFAC (Dortmund). Diese Modelle ermöglichen es, Phasengleichgewichte und Exzessgrößen vorherzusagen, auch wenn das betrachtete System bisher nicht experimentell untersucht wurde. Basis für die Anpassung der …
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Estrategia de parametrización del modelo A-UNIFAC
… En este trabajo de tesis se utiliza el modelo A-UNIFAC para correlacionar y predecir las condicio-nes de equilibrio entre fases en mezclas conteniendo agua y tres familias de compuestos orgánicos típicos del procesa-miento de la biomasa: alcanos, alcoholes y ácidos carboxílicos. El Capítulo 1 de …
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Evaluation of UNIFAC group interaction parameters usijng properties based on quantum mechanical calculations
… group-contribution methods such as ASOG and UNIFAC are widely used for approximate estimation of mixture behavior but unable to distinguish between isomers. Atoms in Molecules (AIM) theory can solve these problems by using quantum mechanics and computational chemistry to compute atomic …
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Erweiterung der Gruppenbeitragsmethode Modified UNIFAC (Dortmund)zur Beschreibung und Vorhersage von Systemen mit ionischen Flüssigkeiten
… der Gruppen-beitragsmethode Modified UNIFAC (Do) auf Systeme mit ionischen Flüssigkeiten zu erweitern. Im experimentellen Teil dieser Arbeit wurde die Datenbasis für Systeme mit ionischen Flüssigkeiten durch systematische Messungen von Aktivitätskoeffizienten bei unendlicher …
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Evaluation und Erweiterung thermodynamischer Modelle zur Vorhersage von Wirkstofflöslichkeiten
… (ideale Mischung, Hansen-Löslichkeitsmodell, UNIFAC, Mod. UNIFAC (Do), COSMO-RS(Ol), NRTL-SAC, Pharma Mod. UNIFAC). Die Anzahl an berechenbaren Löslichkeitsdaten hängt aufgrund modellspezifischer Parameter vom Aktivitätskoeffizientenmodell ab. Der Vergleich mit verfügbaren experimentellen …
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Fundamental solubility study of polycyclic aromatic hydrocarbons in subcritical water and ethanol mixtures
… conditions to be maintained. The UNIQUAC, O-UNIFAC, and M-UNIFAC models were used to correlate the solubilities of PAHs in subcritical conditions. The UNIQUAC model best represents the solubilities of anthracene and p-terphenyl in binary and ternary systems while the O-UNIFAC and M-UNIFAC …
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Evaluation of physical properties of ionic liquids
… was estimated using a new method based on the UNIFAC-VISCO model. The dataset containing 819 experimental viscosity data points for 70 pure ionic liquids was correlated using the modified UNIFAC-VISCO method, thus the interaction parameters and ion VFT parameters were estimated, which were used …
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Measurements of the Molar Heat Capacity and the Molar Excess Enthalpy for Various Alkanolamines in Aqueous Solutions
… UNIQUAC (Universal-Quasi chemical), and UNIFAC (Universal Functional activity coefficient) were used to model the experimental values of the molar excess enthalpies. Among the three above-mentioned models, the modified UNIFAC (Dortmund) was the most accurate for predicting and …
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Vapour-liquid equilibrium studies at atmospheric to moderate pressures
… performance of the predictive methods - Original UNIFAC, a modified version of UNIFAC, and the new novel technique, based on molecular parameters developed from generalised London's potential (GLP) theory.
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Vapor-liquid Equilibrium of Polymer Solutions During Thermal Decomposition of Rigid Foams
… does not occur, it is recommended that the UNIFAC-ZM activity coefficient model be used alone. If phase splitting behavior is observed, it is recommended that the UNIFAC-FV activity coefficient model be used in combination with the Peng-Robinson EOS.</p>
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Experimentelle Bestimmung und Vorhersage des Lösungsmitteleinflusses auf den Gleichgewichtsumsatz und die Kinetik der TAME-Veretherungsreaktion
… der thermodynamischen Modelle VTPR und mod. UNIFAC (Do) konnten sowohl die Gleichgewichtsumsätze, als auch die Reaktionsverläufe in Gegenwart der verschiedenen Lösungsmittel richtig beschrieben werden. Dabei hat sich herausgestellt, dass der Umsatz an TAME in Gegenwart unpolarer Lösungsmittel …
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ΜΕΘΟΔΟΣ ΣΥΝΘΕΣΗΣ Η/ΚΑΙ ΕΠΙΛΟΓΗΣ ΑΡΙΣΤΩΝ ΔΙΑΛΥΤΩΝ ΠΡΟΣ ΕΠΙΤΑΧΥΝΣΗ ΑΝΤΙΔΡΑΣΕΩΝ DIELS-ALDER
… COMPUTING METHOD OF ACTIVITY COEFFICIENTS (NAMED UNIFAC), SOLVENTS EFFECTS WERE STUDIED ON 2 DIELS-ALDER REACTIONS RATE AND GENERAL CONCLUSIONS CAME OUT. THESE CONCLUSIONS WERE PROVED AND EXTENDED TO 9 DIELS-ALDER REACTIONS WITH LITERATURE EXPERIMENTAL DATA. THE CONCLUSIONS ARE LISTED AS …
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Raman Chemometric Method for Fuel Property Prediction
… a two-tier framework that first predicts UNIFAC functional-group weight fractions from chemically-informed Raman features mapped using a curated functional group table and then maps those compositions to bulk properties. The Tier-1 multi-target ANN predicted eleven UNIFAC group weight …
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Modelling approaches for rational solvent selection in drug development, enhancing the solubility prediction of small molecules
… in silico, including: COSMOtherm, NRTL-SAC, UNIFAC, and SAFT-γ Mie.;This work will focus on the use and appraisal of ab initio method COSMOtherm and the application of a "correction factor" using the machine learning algorithm random forest to improve accuracy of predictions. Chapter Two …
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Application of COSMO-SAC to Solid Solubility in Pure and Mixed Solvent Mixtures for Organic Pharmacological Compounds
… Activity Coefficient (NRTL-SAC) model. We find UNIFAC is a more accurate method for predicting VLE behavior than the COSMO-SAC model for many of the systems studied, and that COSMO-SAC predicts solute mole fraction in pure solvents with an average root-mean-squared error (log10(xsol)) of 0.74, …
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Models of gas-liquid solubilities
… Unlike existing prediction methods, for example UNIFAC, the AGAPE method uses only information derived from accessible experimental data and molecular information for pure components. Presently, the AGAPE method has some limitations, namely that the mixtures must consist of small, non-polar …
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BTX extraction by sulfolane in a mixer-settler cascade
… agreement with theoretical predictions using the UNIFAC method. A study was made of the performance of a 10-stage laboratory mixer-settler cascade for the extraction of BTX from a synthetic reformate utilizing sulfolane as a solvent. Murphree stage efficiency decreased with stage number but 99% …
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The separation of hydrogen and carbon monoxide using polymer membranes
… solubility in liquids and that in polymers. The UNIFAC group contribution method is then used to predict gas solubility in liquids. In the second method the polymer Permachor number, developed by Salame, has been correlated with hydrogen and carbon monoxide permeabilities. These correlations are …
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Catalyst immobilization techniques for continuous flow synthesis
… A screening program using the modified UNIFAC (Dortmund) activity coefficient model to evaluate phase splitting behavior has been developed to predict thermomorphic behavior. Calculation of 861 binary solvent combinations results in 43 potential thermomorphic and 44 biphasic solvent …
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A comparison of thermodynamic models for the prediction of phase behavior in aqueous-polymer two-phase systems
… and two group-contribution models (ASOG and UNIFAC) are all discussed. The development of a solvent-electrolyte model (Chen's model) based on local composition theory (in particular the NRTL model) is reviewed, and the subsequent possible modification of this theory for …
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