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mass-transfer
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Proficiency of tellurium extraction in pulsed disc and doughnut columns
, Article Separation Science and Technology (Philadelphia) ; Volume 56, Issue 18 , 2021 , Pages 3092-3105 ; 01496395 (ISSN) ; Torkaman, R ; Torab Mostaedi, M ; Asadollahzadeh, M ; Sharif University of Technology
Taylor and Francis Ltd
2021
Abstract
In this research, the separation of tellurium from selenium was studied from chloride solution by TBP extractant. In the batch experiments, the experimental findings indicated that the feed acidity, TBP concentration, and contact time were optimized to achieve the high separation factor. In continuous mode of pulsed disc and doughnut column, the impacts of operating parameters have been discussed on the distribution coefficients of selenium and tellurium, and mass transfer enhancement. A new model for predicting Koca was proposed in terms of holdup values, Sherwood, Reynolds, and Schmidt numbers, which has an acceptable agreement with the mass transfer data. © 2020 Taylor & Francis Group,...
Lipoxygenase-1 mass-transfer coefficient in aqueous two-phase system using spray extraction column
, Article Industrial and Engineering Chemistry Research ; Volume 44, Issue 19 , 2005 , Pages 7469-7473 ; 08885885 (ISSN) ; Rostami, K ; Kheirolomoom, A ; Sharif University of Technology
2005
Abstract
Extraction of lipoxygenase-1 was investigated by using the aqueous two-phase system formed by sodium sulfate-poly(ethylene glycol)-buffer. The extraction was performed in a 47-mm inner diameter spray column, operating in a semibatch manner. The effects of dispersed-phase flow rate and phase compositions on fractional dispersed-phase hold up (εD) and volumetric masstransfer coefficient (KDa) were respectively studied. It was found that the hold-up and volumetric mass-transfer coefficient increased with an increase in dispersed-phase velocity and decreased with increasing phase composition. Correlations have been developed by nonlinear regression for estimation of fractional dispersed-phase...
Prediction of the Contribution of Mass Transfer During Jet Formation in Liquid-Liquid Extraction Columns
, M.Sc. Thesis Sharif University of Technology ; 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 ; 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...
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 ; 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) ; 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) ; 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) ; 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) ; 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...
Revealing mass transfer and hydrodynamic effects in a PRDC column by using the integration of extraction and separation for molybdenum and tungsten ions from aqueous solution
, Article Chemical Papers ; Volume 74, Issue 12 , 2020 , Pages 4295-4313 ; Torkaman, R ; Torab Mostaedi, M ; Asadollahzadeh, M ; Sharif University of Technology
Springer
2020
Abstract
The present work is performed to assess the hydrodynamic parameters and mass transfer coefficients in a PRDC column for the chemical reaction systems. By considering the selective extraction of molybdenum from tungsten, the extraction parameters and synergistic enhancement factor were interpreted at the batch experiments. In the column experiments, the impacts of operating conditions such as the agitation rate, inlet solvent phase velocity as well as inlet aqueous phase velocity were studied on the drop behavior, overall mass transfer coefficients, and extraction efficiencies. The modified correlations by using relationship of dimensionless numbers were illustrated to estimate the...
The performance of pulsed scale-up column for permeable of selenium and tellurium ions to organic phase, case study: Disc and doughnut structure
, Article Chemical Engineering and Processing - Process Intensification ; Volume 157 , 2020 ; Torkaman, R ; Torab Mostaedi, M ; Asadollahzadeh, M ; Sharif University of Technology
Elsevier B.V
2020
Abstract
A research investigation of the overall mass transfer coefficients, holdup and mean drops of dispersed phase as well as slip and characteristic velocities were carried out in the pulsed scale-up column with disc and doughnut structure for extraction of tellurium and selenium from a hydrochloric acid medium with TBP extractant. The impact of operating conditions containing the pulse intensity, inlet aqueous and solvent phase velocities have been studied on the mass transfer rates, and the special column characteristic. By considering the reactive extraction situations, modified models were derived for predicting of holdup, d32, and slip velocity in this extractor. The axial diffusion model...
Study of the effect of fluid flow on corrosion rate for simple carbon steel in aqueous solution using rotating disk electrode
, Article 18th International Congress of Chemical and Process Engineering, CHISA 2008, Prague, 24 August 2008 through 28 August 2008 ; 2008 ; Mohagheghi, A ; Sharif University of Technology
2008
Abstract
The influence of fluid flow on the corrosion of simple carbon steel ST37 (AISI 1020) in aqueous solution of Bandar-Abbas gas well was studied at 25°C under air-saturated condition. The mechanism and kinetic of corrosion in different hydrodynamic conditions were determined using a rotating disk electrode. Increasing the velocity of rotating disk ≤ 1000 rpm caused an augmentation in corrosion rate from 9.89 to 18.95 mill in./yr. Increasing the velocity beyond 1000 rpm changed the corrosion mechanism so that the activation polarization will control the corrosion process, and the variation in corrosion rates was due to various corrosion mechanisms rather than mass transfer of reactant component....
Evaluation of imperial performance characteristic of turbocharger turbine and compressor
, Article 9th AIAA/ASME Joint Thermophysics and Heat Transfer Conference Proceedings, San Francisco, CA, 5 June 2006 through 8 June 2006 ; Volume 2 , 2006 , Pages 1019-1028 ; 1563478153 (ISBN); 9781563478154 (ISBN) ; Hajilouy, A ; Shahhosseini, M. R ; Sharif University of Technology
2006
Abstract
Performance characteristics of turbocharger turbine and compressor such as efficiency, mass parameter and power are determined experimentally at turbocharger laboratory. Accurate determination of the performance map is significant for manufacturers as well as end users. To this end accurate measurement of test parameters such as temperature, pressure, and speed are required. In this paper an analytic method to predict the measurement uncertainties in turbocharger laboratory, is described. Furthermore the effect of each test parameter on the performance uncertainty is considered. Test parameters that have the most significant influence on the performance uncertainties are identified....
Investigation of a two impinging-jets contacting device for liquid-liquid extraction processes
, Article Chemical Engineering Journal ; Volume 118, Issue 3 , 2006 , Pages 3942-3950 ; 13858947 (ISSN) ; Ebrahimzadeh Zonouzian, S. A ; Dehkordi, A. M ; Sharif University of Technology
Elsevier
2006
Investigating the use of cooling surfaces in solid-state fermentation tray bioreactors: Modelling and experimentation
, Article Journal of Chemical Technology and Biotechnology ; Volume 79, Issue 11 , 2004 , Pages 1228-1242 ; 02682575 (ISSN) ; Roostaazad, R ; Safekordi, A ; Bozorgmehri, R ; Mitchell, D. A ; Sharif University of Technology
2004
Abstract
The effect of wall cooling in tray-type solid-state fermenters was investigated by cultivation of Aspergillus niger ATCC 10 864 on wheat bran. Temperature, moisture, pH and glucoamylase activity in the bed were monitored. Application of the heat exchanger plate reduced the overall water loss but increased the heterogeneity of moisture distribution in the bed. Moisture content increased markedly close to the heat transfer plate while the upper regions of the bed dried out. The thermal conductivity of the bed was measured to be 0.19 Wm-1 K-1. At these conditions and depending on the air flow rate, 58-82% of the metabolic heat was removed via conduction towards the plate. A mathematical model...
Influence of external mass transfer limitation on apparent kinetic parameters of penicillin G acylase immobilized on nonporous ultrafine silica particles
, Article Journal of Bioscience and Bioengineering ; Volume 93, Issue 2 , 2002 , Pages 125-129 ; 13891723 (ISSN) ; Khorasheh, F ; Fazelinia, H ; Sharif University of Technology
Society of Fermentation and Bioengineering
2002
Abstract
Immobilization of enzymes on nonporous supports provides a suitable model for investigating the effect of external mass transfer limitation on the reaction rate in the absence of internal diffusional resistance. In this study, deacylation of penicillin G was investigated using penicillin acylase immobilized on ultrafine silica particles. Kinetic studies were performed within the low-substrate-concentration region, where the external mass transfer limitation becomes significant. To predict the apparent kinetic parameters and the overall effectiveness factor, knowledge of the external mass transfer coefficient, kLa, is necessary. Although various correlations exist for estimation of kLa, in...
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) ; 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) ; 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),...
Quantifying the direct influence of diffusive mass transfer in rarefied gas mixing simulations
, Article Journal of Fluids Engineering, Transactions of the ASME ; Volume 140, Issue 3 , March , 2018 ; 00982202 (ISSN) ; Sabouri, M ; Sharif University of Technology
American Society of Mechanical Engineers (ASME)
2018
Abstract
This work utilizes the direct simulation Monte Carlo (DSMC) calculations and examines the influence of rarefication on the mixing length and effective diffusion coefficient in a two-species mixing problem. There have been efforts in past rarefied mixing flow studies to bridge between the mixing evolution rate and Knudsen number. A careful review of those efforts shows that the past derived relations did not determine the weights of Reynolds (or Peclet) number in the rarefaction influences. Although they indicated that an increase in Knudsen would decrease the mixing length, such reductions were primarily due to the Reynolds (or Peclet) reduction. Therefore, those studies could not explicitly...
Numerical simulation of viscous dissipation in a micropolar fluid flow through a porous medium
, Article Journal of Applied Mechanics and Technical Physics ; Volume 60, Issue 6 , 2019 , Pages 996-1004 ; 00218944 (ISSN) ; Ashraf, M ; Ali, K ; Sharif University of Technology]
Pleiades Publishing
2019
Abstract
Taking into account the effect of viscous dissipation in the energy equation, we numerically explore the flow of an incompressible micropolar fluid with heat and mass transfer through a resistive porous medium between plane channel walls. By exploiting a similarity transformation, the governing partial differential equations are transformed into a system of nonlinear coupled ordinary differential equations, which are solved numerically for various problem parameters by means of quasi-linearization. It is found that the effect of viscous dissipation is to increase the heat and mass transfer rate at both the lower and upper walls of the channel. © 2019, Pleiades Publishing, Ltd