Liquid−Liquid Extraction with an Interphase Chemical Reaction in an Air-Driven Two-Impinging-Streams Reactor:  Effective Interfacial Area and Overall Mass-Transfer Coefficient

2002 ◽  
Vol 41 (16) ◽  
pp. 4085-4093 ◽  
Author(s):  
Asghar Molaei Dehkordi
Keyword(s):  
Mass Transfer ◽  
Transfer Coefficient ◽  
Mass Transfer Coefficient ◽  
Chemical Reaction ◽  
Interfacial Area ◽  
Liquid Extraction ◽  
Liquid Liquid Extraction ◽  
Overall Mass Transfer Coefficient

Experimental Investigation of the Effects of Surfactants on the Mass Transfer in Liquid-Liquid Extraction Equipments

2007 ◽  
Author(s):  
A. Haghdoost ◽  
M. Shah-Alami ◽  
H. Mansouri
Keyword(s):  
Mass Transfer ◽  
Transfer Coefficient ◽  
Mass Transfer Coefficient ◽  
Terminal Velocity ◽  
Liquid Extraction ◽  
Drop Diameter ◽  
Transfer Resistance ◽  
Transfer Rates ◽  
Liquid Liquid Extraction ◽  
Triton X

Mass transfer rates to the drops in liquid-liquid extraction equipment are often likely to be reduced by the presence of surface active contaminants. This reduction in mass transfer is said to be due to a reduction in terminal velocity, and to changes in pattern of internal circulation. A single-drop extraction apparatus was used to investigate the dependency of mass transfer coefficient on the amount of surfactant added in a system of n-butanol/succinic acid/water. Three types of surfactants, SDS, DTMAC and Triton X-100, were used to study their effects on the inhibition of mass transfer in liquid-liquid extraction. The effect of surfactants concentration on extraction percentage, overall mass transfer coefficient, and extra mass transfer resistance was investigated for these surfactants. Also variation of terminal velocity as a function of surfactant concentration and drop diameter were illustrated for both surfactants. Finally these surfactants were compared to each other.

scholarly journals KEBERLAKUAN MODEL HB-GFT SISTEM n-HEKSANA – MEK – AIR PADA EKSTRAKSI CAIR-CAIR KOLOM ISIAN

Konversi ◽  
2013 ◽  
Vol 2 (1) ◽  
pp. 32
Author(s):  
Agus Mirwan
Keyword(s):  
Mass Transfer ◽  
Transfer Coefficient ◽  
Mass Transfer Coefficient ◽  
Flow Rate ◽  
Liquid Extraction ◽  
Extraction Column ◽  
Drop Diameter ◽  
Dispersion Phase ◽  
Liquid Liquid Extraction ◽  
Packing Column

Ekstraksi cair-cair dalam kolom isian merupakan proses pemisahan fasa cair yang memanfaatkan perbedaan kelarutan suatu zat. Tipe ekstraksi ini termasuk kedalam  tipe ekstraksi kolom vertikal tanpa berpengaduk (unagitated) selain kolom semprot (spray) dan kolom pelat. Operasi ekstraksi cair-cair yang baik sangat dipengaruhi oleh karakteristik perpindahan zat terlarut (solute). Karakteristik ini dapat dikuantifikasikan dengan suatu nilai yang disebut dengan koefisien perpindahan massa. Koefisien perpindahan massa ini sangat penting untuk diketahui dalam perancangan kolom ekstraksi cair-cair dan nilainya dapat dicari dengan menggunakan model-model estimasi koefisien perpindahan massa baik di fasa dispersi maupun fasa kontinyu. Penelitian ini bertujuan untuk membuktikan keberlakuan model Handloss-Baros – Garner-Foord-Tayeban (HB-GFT) pada proses ekstraksi cair-cair menggunakan prototipe kolom transparan dan jenis isian berupa bola-bola kecil dengan variasi laju alir fasa kontinyu dan fasa dispersi pada rentang tetesan bersirkulasi (Re = 10 – 200). Dari penelitian ini didapatkan bahwa jenis isian, ukuran tetesan, dan laju alir fasa kedua (dispersi dan  kontinyu) memberikan pengaruh yang cukup signifikan terhadap proses perpindahan massa yang dinyatakan dengan koefisien perpindahan massa keseluruhan (KOD). Data laju alir dan komposisi masing-masing fasa di aliran masuk dan keluar kolom dianalisis dengan menggunakan alat kromatografi gas (GC) yang ditunjukan dengan makin besar laju alir fasa dispersi (Qd), koefisien perpindahan massa keseluruhan (KOD) makin kecil. Hal ini disebabkan bahwa ukuran diameter tetesan disepanjang kolom isian dianggap sama. Dan keberlakuan model HB-GFT untuk dinamika tetesan sirkulasi internal (170<Re<200) merupakan kombinasi terbaik dalam penentuan KOD dengan standar deviasi sebesar 3,2%. Keywords: ekstraksi, kolom isian, perpindahan massa. Liquid-liquid extraction in packed column is a process of liquid phase separation in which a liquid solution (the feed) is contacted with an immiscible or nearly immiscible liquid (solvent). This type of extraction is a kind of vertical column extraction type without agitator (unagitated column) besides spray column and plate column. Good operation of liquid-liquid extraction hardly influenced by solute transfer characteristic. This characteristic can be quantification with a value so-called with mass transfer coefficient. Mass transfer coefficient is importance in order to be known in scheme of liquid-liquid extraction column and the values can be searched by using estimation models of mass transfer coefficient either in dispersion phase and also continue phase.The aim of this research is to prove model applying Handloss-Baros - Garner-Foord-Tayeban (HB-GFT) at liquid-liquid extraction process using transparent column prototype and packing type of small sphere with various of flow rate continue phase and dispersion phase at circulation drop spread (Re = 10 - 200). From this research got that packing type, droplet size, and flow rate phase (dispersion and continue) gives influence that is enough significant to mass transfer process that expressed with overall mass transfer coefficient (KOD). Flow rate and composition each phase in inlet and outlet column data are analyzed by using gas chromatography equipment (GC) that showed more and more big dispersion phase (Qd) flow rate, mass transfer coefficient (KOD) more and more small. This caused that drop diameter measure along the length of packing column assumed to be same. And model applying HB-GFT for internal circulation drop dynamics (170<Re<200) is best combination in determination of KOD with deviation standard equal to 3,2%. Keywords: extraction, packing column, mass transfer

Modeling Vapor Transport in a Hollow Fiber Membrane Humidifier Using ε-NTU Approach

2020 ◽  
Author(s):  
Hoang Nghia Vu ◽  
Xuan Linh Nguyen ◽  
Sangseok Yu
Keyword(s):  
Heat Transfer ◽  
Mass Transfer ◽  
Fuel Cell ◽  
Relative Humidity ◽  
Transfer Coefficient ◽  
Mass Transfer Coefficient ◽  
Water Content ◽  
Vapor Transport ◽  
Overall Mass Transfer Coefficient ◽  
Mass Exchanger

Abstract In a fuel cell vehicle, the water content of the gas supply within certain ranges plays a key role in improving the performance of a proton exchange membrane. The lower limit of water content in the air supply is to avoid the problem of drying-out, while the upper prevents flooding. Water management can be accomplished by a membrane humidifier which allows water vapor to permeate the mixture from the side having the higher water concentration, moving to the other side of the membrane. In this study, the variation in water content collected at the outlet of a membrane humidifier is investigated with a one-dimensional mass exchanger model and various operating variables. The vapor concentration of outlet flows is affected by operating temperature and relative humidity of the membrane humidifier. Relative humidity of the dry side at the point of outlet flow, to be supplied to the fuel cell module, is the key characteristic. The analogy of the effectiveness-NTU approach for heat transfer is used to analyze the characteristics of the mass exchanger. Mass flux through the membranes is estimated with an overall mass transfer coefficient which represents vapor transport characteristics moving through the membrane module. This coefficient has a similar role to the overall heat transfer coefficient in heat exchanger analysis. This parametric study is conducted to understand the effects of different variables. The Effectiveness-NTU methodology of mass transfer uses the overall mass transfer coefficient and the mass transfer rate, as evaluated experimentally. Simulink software is then employed to deliver outcomes of the model for different operating conditions.

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