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    Solid-Liquid Mass Transfer in the Annular Region of a Taylor-Couette Contacting Device

    , M.Sc. Thesis Sharif University of Technology Faraji Dizaji, Naeimeh (Author) ; Molaei Dehkordi, Asghar (Supervisor)
    Abstract
    Vortex flow reactor (VFR) is used for biochemical reactions and separation applications. By using the second flow regime, called Taylor-Couette flow, VFR provides high amounts of mass transfer and mixing for biological components sensitive to shear stress. Mass transfer in a bench-scale Taylor-Couette contactor with a radius ratio, equal to 0.77 and an aspect ratio, equal to 30.7 was studied for solid particles dissolution. The working fluid was water and the suspended particles were benzoic acid. In this project the concentration of fluid phase was measured by injection of definite amount of the solid particles in to the contactor and sampling in different time intervals and the effects of... 

    A new method to calculate efficiency of randomly-packed distillation columns and its comparison with the methods utilized in ASPEN Plus

    , Article Fuel Processing Technology ; Volume 96 , 2012 , Pages 65-73 ; 03783820 (ISSN) Sadeghifar, H ; Sadeghifar, A ; Sharif University of Technology
    2012
    Abstract
    In this paper, a unique and applicable method was developed for calculation of efficiency (and mass and heat transfer coefficients) of randomly-packed distillation columns. This method has potential advantages; e.g., unlike all the available methods, it can calculate efficiency without using any empirical mass transfer and hydraulic correlations, and without the need to estimate the operational and hydraulic parameters of an operating column. It, therefore, will be free of errors and limitations of such empirical items and can be used for efficiency calculation of any random packing including new ones. Along with an analysis of the proposed method, the paper also presents a thorough analysis... 

    Evaluation of interfacial mass transfer coefficient as a function of temperature and pressure in carbon dioxide/normal alkane systems

    , Article Heat and Mass Transfer/Waerme- und Stoffuebertragung ; Volume 51, Issue 4 , April , 2015 , Pages 477-485 ; 09477411 (ISSN) Nikkhou, F ; Keshavarz, P ; Ayatollahi, S ; Raoofi Jahromi, I ; Zolghadr, A ; Sharif University of Technology
    Springer Verlag  2015
    Abstract
    CO2 gas injection is known as one of the most popular enhanced oil recovery techniques for light and medium oil reservoirs, therefore providing an acceptable mass transfer mechanism for CO2–oil systems seems necessary. In this study, interfacial mass transfer coefficient has been evaluated for CO2–normal heptane and CO2–normal hexadecane systems using equilibrium and dynamic interfacial tension data, which have been measured using the pendant drop method. Interface mass transfer coefficient has been calculated as a function of temperature and pressure in the range of 313–393 K and 1.7–8.6 MPa, respectively. The results showed that the interfacial resistance is a parameter that can control... 

    The effect of nanoparticles on the mass transfer in Liquid–Liquid extraction

    , Article Chemical Engineering Communications ; Volume 202, Issue 5 , Sep , 2015 , Pages 600-605 ; 00986445 (ISSN) Mirzazadeh Ghanadi, A ; Heydari Nasab, A ; Bastani, D ; Seife Kordi, A. A ; Sharif University of Technology
    Taylor and Francis Ltd  2015
    Abstract
    This article investigates the effect of nanoparticles on mass transfer in the liquid–liquid extraction for the chemical system of n-butanol–succinic acid–water. For this purpose, nanofluids containing various concentrations of ZnO, carbon nanotubes (CNT), and TiO2 nanoparticles in water, as base fluid, were prepared. To examine the flow mode effect on mass transfer rate, different fluid modes including dropping and jetting were employed in the process. Results show that mass transfer rate enhancement depends on the kinds and the concentration of nanoparticles and the modes of flow. It was observed that after adding nanoparticles, the mass transfer rate significantly increases up to two-fold... 

    Investigation of Mass Transfer in Liquid-Liquid System in the Presence of Nanosized Particles

    , M.Sc. Thesis Sharif University of Technology Nakhaeipour, Fahimeh (Author) ; Bastani, Dariush (Supervisor)
    Abstract
    The main objective of this project is to study the effect of the presence of nanoparticles on mass transfer in liquid-liquid systems. To do this research, TiO2/water, Al2O3/water, CNTs/water and CNTs/toluene have been used as nanofluids. The experiments of TiO2/water nanofluid were been carried out in water-acetone-toluene system at two weigh percents of TiO2 nanoparticles. The result showed that mass transfer decreased in 0.5wt% of TiO2, compared to base fluid, and it increase in 1 %wt. Also in 0.5%wt the decrease in interfacial tension decreased diameter of drops and as a result mass transfer decreased too. In 1%wt the increase in viscosity increased the diameter of drops and then the... 

    Investigation the effect of super hydrophobic titania nanoparticles on the mass transfer performance of single drop liquid-liquid extraction process

    , Article Separation and Purification Technology ; Volume 176 , 2017 , Pages 107-119 ; 13835866 (ISSN) Hatami, A ; Bastani, D ; Najafi, F ; Sharif University of Technology
    Abstract
    Hydrophobic titania nanoparticles were synthesized by a novel in situ sol-gel method and applied in a single drop liquid-liquid extraction column to enhance the overall dispersed-phase mass transfer coefficient (Kod). The chemical system of toluene, acetic acid and water was used, and the direction of solute (acetic acid) mass transfer was from dispersed phase, including: toluene and acetic acid to the continuous phase of water. For such system, much of the mass transfer resistance exists in the dispersed phase, which is nonpolar organic liquid. Hence, modified titania nanoparticles (MTNP's), prepared by sol-gel route, in five different concentrations of 0.001–0.005 wt.% were added in the... 

    The investigation of natural super-cavitation flow behind three-dimensional cavitators: Full cavitation model

    , Article Applied Mathematical Modelling ; Volume 45 , 2016 , Pages 165-178 ; 0307904X (ISSN) Kadivar, E ; Kadivar, Erfan ; Javadi, K ; Javadpour, S. M ; Sharif University of Technology
    Elsevier Inc 
    Abstract
    In this study, natural super-cavitating flow around three different conical cavitators with wedge angles of 30°, 45° and 60° is investigated. We apply the k−ϵ turbulence model and the volume of fluid (VOF) technique to numerically study the three-dimensional cavitating flow around the cavitators. The turbulence approach is coupled with a mass transfer model which is implemented into the finite-volume package. Simulations are performed for different cavitation numbers. Finally, the effects of some important parameters such as the cavitation index, inlet velocity, Froude number and wedge angle of cavitators on the geometrical characteristics of the super-cavities are discussed. Our numerical... 

    Application of power law logistic model to growth kinetics of bacillus licheniformis MS3 on a water- insoluble substrate

    , Article Chemical Engineering Communications ; Volume 201, Issue 11 , 06 June 2014 , Pages 1514-1525 Biria, D ; Maghsoudi, E ; Roostaazad, R ; Sharif University of Technology
    Abstract
    The power law logistic model was utilized to investigate the growth of a hydrocarbon assimilating bacterium on a water-insoluble substrate. To achieve this end, population dynamics of Bacillus licheniformis MS3 in a medium containing n-decane as the sole carbon source was monitored for 30 h. Different initial biosurfactant concentrations and shaking rates were employed to examine the role of mass transfer in the cell growth and the consequent hydrocarbon biodegradation. The amount of n-decane degraded in the system was detected by gas chromatography at the end of the incubation period. The results revealed that when mass transfer limitations were lessened through addition of an initial... 

    Investigation of mass transfer coefficient under jetting conditions in a liquid-liquid extraction system

    , Article Iranian Journal of Chemistry and Chemical Engineering ; Volume 29, Issue 1 , 2010 , Pages 1-12 ; 10219986 (ISSN) Nosratinia, F ; Omidkhah, M. R ; Bastani, D ; Saifkordi, A. A ; Sharif University of Technology
    Abstract
    In this research mass transfer coefficient under jetting regime in different directions (from dispersed to continuous and continuous to dispersed phase) has been studied using an experimental setup. n-Butanol-succinic acid-water with low interfacial tension has been selected as experimental chemical system. The effects of various parameters such as jet velocity, nozzle diameter and the height of the continuous phase above the nozzle, on mass transfer coefficient have been investigated. A correlation has also been derived in order to predict the mass transfer coefficient as a function of physical properties of both phases and aforementioned parameters. Based on the experimental results, mass... 

    Mass-transfer enhancement in single drop extraction in the presence of magnetic nanoparticles and magnetic field

    , Article AIChE Journal ; Volume 62, Issue 12 , 2016 , Pages 4466-4479 ; 00011541 (ISSN) Vahedi, A ; Molaei Dehkordi, A ; Fadaei, F ; Sharif University of Technology
    John Wiley and Sons Inc  2016
    Abstract
    Magnetite nanoparticles with an average particle size of 28.8 nm were synthesized, coated with oleic acid, and characterized using various techniques such as DLS, FT-IR, SEM, XRD, VSM, and UV-Vis analysis. A nanofluid consisting of synthesized nanoparticles and 5 wt % acetic acid in toluene as the dispersed phase was prepared and used in the chemical test system, Toluene-Acetic Acid-Water, for the single drop extraction in the presence and absence of an external oscillating magnetic field. Influences of various operating and design parameters such as nanoparticle concentration, drop diameter, and the applied current and frequency on the overall mass-transfer coefficients for the... 

    Infrared thin layer drying of saffron (Crocus sativus L.) stigmas: Mass transfer parameters and quality assessment

    , Article Chinese Journal of Chemical Engineering ; 2016 ; 10049541 (ISSN) Torki Harchegani, M ; Ghanbarian, D ; Maghsoodi, V ; Moheb, A ; Sharif University of Technology
    Chemical Industry Press 
    Abstract
    Saffron is the most precious and expensive agricultural product. A dehydration treatment is necessary to convert Crocus sativus L. stigmas into saffron spice. To the best of our knowledge, no information on mass transfer parameters of saffron stigmas is available in the literature. This study aimed at investigating the moisture transfer parameters and quality attributes of saffron stigmas under infrared treatment at different temperatures (60, 70, ..., 110°C). It was observed that the dehydration process of the samples occurred in a short accelerating rate period at the start followed by a falling rate period. The effective moisture diffusivity and convective mass transfer coefficient were... 

    Infrared thin layer drying of saffron (Crocus sativus L.) stigmas: Mass transfer parameters and quality assessment

    , Article Chinese Journal of Chemical Engineering ; Volume 25, Issue 4 , 2017 , Pages 426-432 ; 10049541 (ISSN) Torki Harchegani, M ; Ghanbarian, D ; Maghsoodi, V ; Moheb, A ; Sharif University of Technology
    Chemical Industry Press  2017
    Abstract
    Saffron is the most precious and expensive agricultural product. A dehydration treatment is necessary to convert Crocus sativus L. stigmas into saffron spice. To the best of our knowledge, no information on mass transfer parameters of saffron stigmas is available in the literature. This study aimed at investigating the moisture transfer parameters and quality attributes of saffron stigmas under infrared treatment at different temperatures (60, 70, …, 110 °C). It was observed that the dehydration process of the samples occurred in a short accelerating rate period at the start followed by a falling rate period. The effective moisture diffusivity and convective mass transfer coefficient were... 

    Prediction of the Contribution of Mass Transfer During Jet Formation in Liquid-Liquid Extraction Columns

    , M.Sc. Thesis Sharif University of Technology Taleshi, Navid (Author) ; Sayf Kordi, Ali Akbar (Supervisor)
    Abstract
    There are many different opinions about the mass transfer contribution during jet formation in liquid - liquid extraction columns, and this could impact on their design. In this work, using experimental data obtained in two RDC columns and unpublished data of the jet mass transfer coefficients, mass transfer can be predicted during jet formation. The jet length and diameter were anticipated by using existing relations, and then the jet mass transfer coefficient was predicted, jet mass transfer rate and total column mass transfer rate were calculated and finally the contribution of mass transfer during jet formation in the column was predicted. Mass transfer contribution in the jet in various... 

    , M.Sc. Thesis Sharif University of Technology Sarrafan, Kiana (Author) ; Bastani, Daruoosh (Supervisor)
    Abstract
    In liquid-liquid extraction, as in gas absorption, two phases must be brought into good contact to permit transfer of material. The presence of nanoparticles in liquid phase can enhanced the rate of gas-liquid mass transfer. The benefits of nanofluids can be used to enhance the heat and mass transfer of liquid-liquid extraction. Standard test system with low interfacial tension that recommended by EFCE: n-butanol/water/succinic acid, was used in this project. The CNTs/n-butanol that was saturated of water used as dispersed phase. Water and succinic acid used as continuous phase and solute. Since there is no chemical reaction to take place between CNTs and n-butanol, In order to obtain well... 

    Experimental Investigation of Mass Transfer by Droplet Using Image Processing

    , M.Sc. Thesis Sharif University of Technology Babak, Pirooz Hashemi (Author) ; Firoozabadi, Bahar (Supervisor) ; Afshin, Hossein (Co-Advisor)
    Abstract
    Wide and varied aspects of droplet motion due to its increasing application in various fields has attracted much attention. Analysis of mass transfer from the liquid drop into the other fluid, such as complex and intriguing problems in fluid mechanics, which is very important. Many experimental and numerical studies have been carried out in this case that the evelopment of laboratory equipment and software, are rapidly growing.
    In this study, given the importance of this issue, experimental study on mass transfer in fluid systems solution droplet liquid - liquid extraction, have been considered. Different methods have been discussed to date. In the present study, using image processing... 

    Effects of contaminants on the mass-transfer characteristics of a two-impinging-streams gas-liquid reactor

    , Article Chemical Engineering and Technology ; Volume 34, Issue 11 , 2011 , Pages 1797-1806 ; 09307516 (ISSN) Dehkordi, A. M ; Savari, C ; Sharif University of Technology
    Abstract
    The mass-transfer characteristics of a new type of two-impinging-streams reactor (TISR) was studied by means of sodium sulfite solution as the liquid phase and air as the gas phase, in the presence and absence of various types of surface-active agents (SAAs). The influences of anionic, cationic, and nonionic SAAs on the specific interfacial area and overall volumetric mass-transfer coefficient obtained in the TISR were investigated. It was found that the presence of a little amount of the above-mentioned contaminants increases the specific interfacial area and decreases the overall volumetric mass-transfer coefficient. On the basis of the experimental results obtained for various types of... 

    Analytical and semi-analytical kinetics models for design and optimization of double-resistance resin in pulp and carbon in pulp processes with both reversible and irreversible nature

    , Article Canadian Journal of Chemical Engineering ; Volume 96, Issue 11 , 2018 , Pages 2461-2474 ; 00084034 (ISSN) Naderi, A ; Outokesh, M ; Ahmadian Koudakan, P ; Ghoddocynejad, D ; Saberyan, K ; Sharif University of Technology
    Wiley-Liss Inc  2018
    Abstract
    The current study was aimed at developing a package of “model + algorithm” for the design of resin in pulp (RIP) and carbon in pulp (CIP) processes of gold, uranium, and base metals. For this purpose, we first formulated a double-resistance model for irreversible adsorption (accompanied by chemical reaction) in CSTRs, and modified the McKay et al. semi-analytical model for reversible uptake in a similar system. We then devised two algorithms for the design and optimization of reversible and irreversible RIP and CIP cascades. The developed algorithms were applied on the extraction of copper, uranium, and gold. The packages are able to specify the optimum number of stages, reactor volume (V),... 

    Mass Transfer Modeling while Formation of Liquid Jet to another Liquid

    , M.Sc. Thesis Sharif University of Technology Safarirad, Mohammad Reza (Author) ; Bastani, Darioush (Supervisor)
    Abstract
    Liquid-liquid extraction is one of most important processes in chemical industries. So determination of operating condition effects is very critical. In this thesis we modeled concentration profile in the jet via mathematical equations and compare with experimental data. The major problem in concentration profile and solving equations is lack of knowledge in velocity profile within the jet was formed. Therefore, different flow models such as piston flow model, parabolic flow model, vortex flow model and a cone flow model was used and terminal concentrations inside the jet compared with laboratory values. Results shows the most accurate model to predict the flow concentration along the... 

    Experimental and CFD Study of Physical Properties Effect on Hydrodynamic and Mass Transfer Coefficient of Single Drops

    , M.Sc. Thesis Sharif University of Technology Davari Moghaddam, Abbas (Author) ; Bastani, Daruoosh (Supervisor)
    Abstract
    In present study, it is tried to investigate the effect of physical properties on hydrodynamic and overall mass transfer coefficient of single drops using different experiments and then simulation of drop motion with OpenFOAM software version 1.7.1. the systems were choosen are toluene/acetone/water and n-butanol/succinic acid/water which their interfacial tensions are 36 and 1.6 mN/m respectively. Various type of nozzles have been used for produce of 1.5, 2, 3 and 4 millimeter drops. The results show that in absence of solute component, the rising velocity of toluene drops in each size is higher than rising velocity of butanol drops inside the water between 25 to 75 percent. But with... 

    Simulation of Flow and Mass Transfer in Microfluidic Systems of Human Body

    , Ph.D. Dissertation Sharif University of Technology Saadatmand, Maryam (Author) ; Abd Khodaei, Mohammad Jafar (Supervisor) ; Farhadi, Fathollah (Supervisor) ; Pishvaie, Mahmoud Reza (Supervisor)
    Abstract
    The effects of gravity and inertia dominate our experiences of the physical world. But as systems are reduced in size, phenomena such as diffusion, surface tension and viscosity become ever more important; at the microscale they can dominate and result in a world that operates very differently from the macroscopic world. Kidney is one of the vital organs in which fluid and mass transfer occur between blood flow in microvessels and urine in microchannels called nephron. The present work is aimed at applying microchannel theory to study renal system. First, a n efficient numerical orthogonal collocation method has been employed to solve the steady-state formulation of electrolyte transport in...