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ethanol-water
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A general model for multicomponent transport in nonporous membranes based on Maxwell-Stefan formulation
, Article Chemical Engineering Communications ; Volume 191, Issue 4 , 2004 , Pages 460-499 ; 00986445 (ISSN) ; Farhadpour, F. A ; Soltanieh, M ; Sharif University of Technology
Taylor and Francis Ltd
2004
Abstract
A "general" model of membrane transport was formulated using the mechanistic Maxwell-Stefan approach and generalized driving forces, which included the contribution from the various internal and external driving forces. Transient models of dialysis and pervaporation were developed that used exactly the same general model to describe the transport through the membrane. In this model, the bulk solution/polymer equilibria were described by a modified Flory-Huggins model, and the concentration dependence of ternary Maxwell-Stefan diffusivities was described by a natural extension of the binary Vignes relationship to a multicomponent system. A notable advantage of the general model lies in the...
Multicomponent transport across nonporous polymeric membranes
, Article Desalination ; Volume 144, Issue 1-3 , 2002 , Pages 93-101 ; 00119164 (ISSN) ; Farhadpour, F. A ; Soltanieh, M ; Sharif University of Technology
Elsevier
2002
Abstract
The theoretical description of multicomponent transport across nonporous polymeric membranes was investigated using two alternative frameworks: the phenomenological approach of irreversible thermodynamics and the mechanistic Stefan-Maxwell formulation. The transport models developed account for potential equilibrium and/or kinetic coupling of fluxes and the contribution of diffusion induced non-selective flow within the polymer. The models were validated against transient dialysis and pervaporation data for the {ethanol-water}/silicone rubber system. A critical assessment was obtained by recovering the model parameters from the dialysis data and using the same parameters to predict the...
Extending application of Dehaghani Association Equation of State for Modeling Phase Behavior of Water-Alcohol Systems
, Article Fluid Phase Equilibria ; Volume 482 , 2019 , Pages 126-133 ; 03783812 (ISSN) ; Badizad, M. H ; Sharif University of Technology
Elsevier B.V
2019
Abstract
This paper concerns extending applicability of Dehaghani association equation of state (in short DA-EOS) to model non-ideality in phase behavior caused by hydrogen bonding. Advantageously, this equation only needs two and one parameters to treat self- and cross association, respectively, which were determined for methanol/water and ethanol/water mixture in this study. In this respect, DA was coupled with PR and SRK EOS to account for physical interaction between molecules. Notably, DA-PR persistently provides more accurate prediction than DA-SRK for both aqueous methanol and ethanol solutions
A study of the electrophoretic deposition of bioactive glass-chitosan composite coating
, Article Ceramics International ; Volume 38, Issue 1 , January , 2012 , Pages 471-476 ; 02728842 (ISSN) ; Afshar, A ; Sharif University of Technology
2012
Abstract
Bioactive glass is coated on implant's surface to improve corrosion resistance and osseointegration, when placed in the body. Bioactive glass particles were synthesized through a sol-gel process and deposited along with chitosan to form a composite coating on a stainless steel substrate using electrophoretic deposition technique. Stable suspensions of chitosan-bioactive glass were prepared using bioactive glass particles (<1 μm) and 0.5 g/l chitosan solution. The influence of ethanol-water ratio on deposition yield was investigated. For all process conditions, best results were achieved with suspension of 30 vol% water in ethanol-water containing 2 g/l bioactive glass. FTIR studies showed...
Application of a new gibbs energy equation to model a distillation tower for production of pure ethanol
, Article Chemical Engineering and Technology ; Volume 34, Issue 10 , 2011 , Pages 1715-1722 ; 09307516 (ISSN) ; Pazuki, G ; Vossoughi, M ; Hemmati, S ; Saboohi, Y ; Sharif University of Technology
Abstract
A steady-state equilibrium-stage model based on MESH equations was proposed to simulate saline extractive distillation columns. The interaction parameters between each component of water-CaCl 2 and ethanol-water were obtained from mean ionic activity coefficients and vapor-liquid equilibrium (VLE) experimental data. Additionally, the interaction coefficients for the ethanol-CaCl 2 pair were fitted to experimental VLE data which were reported by Nishi for the ethanol-water-CaCl 2 system. It should be noted that adjustable parameters between each pair were considered to be temperature dependent. The results confirmed that the proposed model could accurately predict the experimental...
Model-based analysis for kinetic complexation study of Pizda and Cu(II)
, Article Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy ; Volume 70, Issue 3 , August , 2008 , Pages 674-681 ; 13861425 (ISSN) ; Maeder, M ; Jalali Heravi, M ; Norman, S. E ; Sharif University of Technology
2008
Abstract
In the present work, the multivariate kinetic complexation of a new synthesized ligand, 1-(2″-hydroxyl cyclohexyl)-3′-[aminopropyl]-4-[3′-aminopropyl]piperazine (Pizda) and Cu2+ in 50% ethanol-water solution is investigated using the UV-vis stopped-flow technique and state-of-the-art multi-wavelength numerical analysis. Model-based least squares fitting analysis or hard modeling is a specific part of chemometrics which is based on mathematical relationships for describing the measurements. Some recent developments include the incorporation of the effects of non-ideal experimental conditions into the fitting algorithm so it can substantially simplify experimental procedures. In this study no...