scholarly journals Ultrasonic Intensification of Mass Transfer in Organic Acid Extraction

Processes ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 15
Author(s):  
Oleg M. Gradov ◽  
Yulia A. Zakhodyaeva ◽  
Inna V. Zinov’eva ◽  
Andrey A. Voshkin
Keyword(s):  
Mass Transfer ◽  
Acoustic Pressure ◽  
Continuous Phase ◽  
Maximum Efficiency ◽  
Dispersed Phase ◽  
Phase System ◽  
Acid Extraction ◽  
Radial Vibrations ◽  
Spherical Droplet ◽  
Membrane Technique

The mechanism of ultrasonic extraction was discovered and analyzed in detail for the liquid membrane technique from the consideration of the specific features of the radial vibrations of a droplet of the dispersed phase placed into an immiscible continuous phase subjected to ultrasonic irradiation. Analytical formulas were derived for the rate of mass transfer as a function of the amplitude of acoustic pressure oscillations and the time of ultrasonic treatment of an extraction system. Conditions for achieving the maximum efficiency of the extraction of a substance under the stimulating effect of ultrasound were analyzed. A nonlinear equation was derived for the radial vibrations of a spherical droplet of the dispersed phase in an immiscible continuous phase under forcing in the form of acoustic pressure periodically changing with time. Experimental study of the dependence of sulfosalicylic acid distribution on time in an aqueous two-phase system with ultrasound shows good agreement of experimental results with the calculations performed.

Mass Transfer Performance of a Novel Structured Packing for Liquid-Liquid Extraction

2011 ◽  
Vol 391-392 ◽  
pp. 1469-1473
Author(s):  
Yin Long Bao ◽  
Chun Jiang Liu ◽  
Xi Gang Yuan
Keyword(s):  
Mass Transfer ◽  
High Efficiency ◽  
Continuous Phase ◽  
Liquid Extraction ◽  
Dispersed Phase ◽  
Phase System ◽  
The Novel ◽  
Structured Packing ◽  
Liquid Liquid Extraction ◽  
Transfer Unit

The flow pattern of the dispersed phase through three types of packings, 700Y rhombus mesh frame packing (RMFP), 350Y polypropylene corrugated sheet packing (PPCSP) andФ16mm plum flower mini ring (PFMR), was observed. According to the characteristics of solvent extraction, a novel hybrid structured packing, consisting of 700Y RMFP and 350Y PPCSP, was developed for liquid-liquid extraction. The mass transfer efficiencies of the novel hybrid structured packing andФ16mm PFMR were investigated in a 150mm diameter column, working with the 30% tributyl phosphate-kerosene (dispersed phase) / acetic / water (continuous phase) system. It is found that the apparent height of mass transfer unit of the hybrid structured packing is 21% smaller than that ofФ16mm PMFR in average under the same experimental condition. It can be concluded that the hybrid structured packing is a high-efficiency packing for liquid-liquid extraction.

scholarly journals KOEFISIEN PERPINDAHAN MASSA VOLUMETRIS KESELURUHAN PADA EKSTRAKSI Cu DARI LARUTAN CuSO4.5H2O DENGAN TRIRUTYL PHOSPHATE-KEROSIN DALAM DOUBLE-STAGE MIXER-SETTLER

2018 ◽  
Vol 7 (1) ◽  
pp. 731
Author(s):  
Panut Mulyono
Keyword(s):  
Aqueous Solution ◽  
Mass Transfer ◽  
Transfer Coefficient ◽  
Mass Transfer Coefficient ◽  
Tributyl Phosphate ◽  
Continuous Phase ◽  
Hole Diameter ◽  
Extraction Column ◽  
Dispersed Phase ◽  
Dilute Aqueous Solution

Copper has been extracted by trtbuthyl phosphate-kerosene from a dilute aqueous solution with a double- stage mixer-settler extraction column. The extraction column used in this experiment was made of glass. The mixer diameter was equal to the diameter of settler was 13 cm. Both the mixer and settler heights were 8 cm. Drop coalescer was mounted in the middle of mixer and settler separator. The diameter of drop coalescer was 6 cm with the thickness of 1 cm. The hole diameter of drop coalescer was 1 mm The stirrer used in this experiment was cross flat blade with the diameter and width of the impeller was 6 cm and 8 mm, respectively. The overall volumetric coefficient of mass transfer (Kca) increased by increasing the flowrate of the continuous phase (Lc) at the constants stirring speed (N) and flowrate of the dispersed phase (Ld). The increase of Lc from 4.1634 cm3/second to 17.9436 cm3/second increased the Kca value from 6.6387x10-5/second to 23.1561x10-5/second or 248.8% The value of Kca was also increase by increasing N at the constant values of Lc and Ld Thie increase of N from 3.3333 rps to 8.3333 rps increased the Kca value from 6.0288x10-5/second to 6.6387x10-5/second or 10.1%.Keywords: Mass Transfer Coefficient, Extraction, Copper, Double-Stage Mixer-SettlerAbstrak Penelitian ini mempelajari perpindahan massa antar fasa pada ekstraksi Cu dart larutan CuSO4.5H2O dengan menggunakan pelarut tributyl phosphate dalam kerosin yang dilakukan dalam kolom ekstraksi double-stage mixer-settler yang dtsusun vertikal. Kolom ekstraksi mixer-settler dibuat darti gelas dengan diameter mixer sama dengan diameter sealer, yaitu 13 cm. Tinggi mixer juga sama dengan tinggt settler, yaitu 8 cm. Diameter drop coalescer 8 cm, tebal 1 cm, dan diameter lubangnya 1 mm. Pengaduk yang digunakan berbentuk flat blade dengan diameter 6 cm dan lebar blade 8 mm. Koeftsien perpindahan massa volumetris keseluruhan (Kca) naik dengan naiknya kecepatan alir fasa kontinyu (Lc) pada kecepatan putaran pengaduk (N) dan kecepatan alir fasa dispersi (Ld) tetap. Kenatkan nilai Lc dart 4,1634 cm3/detik menjadi 17,9436 cm3/detik meningkatkan nilai Kca dart 6,6387x10-5/detik menjadi 23,1561x10-5/detik atau 248,8% Kca juga naik dengan naiknya N pada Lc dan Ld yang tetap. Kenaikan nilai N dart 3,3333 rps menjadi 8,3333 rps meningkatkan nilai Kca dart 6,0288x10-5/detik menjadt 6,6387x10-5/detik atau 10,1%.Kata Kunci : Koefesien Perpindahan Massa, Ekstraksi, Tembaga, Double-Stage Mixer-Settler

scholarly journals Recovery of ascorbic oxidoreductase from crude extract with an aqueous two-phase system in a perforated rotating disc contactor

2004 ◽  
Vol 47 (5) ◽  
pp. 821-826 ◽  
Author(s):  
Ana Lúcia Figueiredo Porto ◽  
Leonie Asfora Sarubbo ◽  
Keila Aparecida Moreira ◽  
Homero José Farias de Melo ◽  
José Luís Lima-Filho ◽  
...  
Keyword(s):  
Mass Transfer ◽  
Phase Velocity ◽  
Crude Extract ◽  
Separation Efficiency ◽  
Dispersed Phase ◽  
Phase System ◽  
Transfer Coefficients ◽  
Rotating Disc ◽  
Two Phase ◽  
Rotating Disc Contactor

A continuous perforated rotating disc contactor was used to extract the enzyme ascorbic oxidoreductase (E.C.1.10.3.3) from crude extract of Curcubita maxima with an aqueous two-phase system of poly (ethylene glycol) and phosphate salts. The effect of dispersed phase velocity on either protein mass transfer coefficients or separation efficiency at 1, 2 and 3 mL/min was studied. An increase of the mass transfer coefficients was observed with the dispersed phase velocity, while the separation efficiency showed a small decrease with the increase of this parameter. The experimental results obtained during continuous extraction showed that the ascorbic oxidoreductase activity was partitioned preferentially into the salt-rich phase in all conditions studied. The best recovery of enzyme activity was 236%, with a purification factor of 34 in flow rates of 1 mL/min for dispersed phase.

scholarly journals Hydrodynamics and mass transfer in Kühni extraction columns

2021 ◽  
pp. 14-14
Author(s):  
Milan Sovilj ◽  
Momcilo Spasojevic
Keyword(s):  
Mass Transfer ◽  
Transfer Coefficient ◽  
Mass Transfer Coefficient ◽  
Dispersed Phase ◽  
Drop Diameter ◽  
Phase System ◽  
Rotor Speed ◽  
Empirical Correlations ◽  
Dimensionless Numbers ◽  
Transfer Direction

This work provides a review of hydrodynamic characteristics and mass transfer in the K?hni extraction columns. The experiments, as reported in the literature, were performed in the presence and absence of mass transfer. The results showed that the Sauter mean drop diameter was strongly affected by the rotor speed and interfacial tension, whereas the effects of the dispersed and continuous velocities were negligible. Empirical correlations for the Sauter mean drop diameter, taken from the literature, were discussed. It was experimentally determined that the dispersed-phase holdup depended to a great extent on the rotor speed, mass transfer direction between the phases, physical characteristics of fluids in the liquid-liquid system, and the dispersed-phase flowrate whereas it increased with the increase in mixing in the two-phase system and the ratio of phase flowrates. On the other hand, it has been shown that the mass transfer rate increases with increasing the level of back mixing. It was found that the mass transfer coefficient depends on the rotor speed and the direction of mass transfer between the phases. At the same time, it has been shown that the mass transfer coefficient depends relatively little on the phase flowrates. An empirical correlation was proposed for prediction of the overall mass transfer coefficient based on dimensionless numbers. Also, novel empirical correlations for prediction of the Sherwood number in the continuous phase were presented based on the dispersed-phase holdup, Reynolds number, and mass transfer direction between the phases. Empirical correlations based on dimensionless numbers can be considered as a useful tool for the design of the K?hni columns.

scholarly journals Dinamika tetes ekstraksi cair-cair sistem air-metil etil keton (mek)-heksan dalam kolom isian

2018 ◽  
Vol 9 (3) ◽  
pp. 99
Author(s):  
Agus Mirwan ◽  
Danu Ariono
Keyword(s):  
Mass Transfer ◽  
Flow Rate ◽  
Transfer Process ◽  
Mass Transfer Process ◽  
Continuous Phase ◽  
Column Height ◽  
Dispersed Phase ◽  
Drop Diameter ◽  
Raschig Ring ◽  
Drop Dynamics

Mass transfer process occurs as effect of contact between continuous phase from above and dispersed phase from underside column. With existence of size and type of packing in column, that caused interfacial area to become bigger and residence time more and older so that improvement of mass transfer process. The aim of this research is to observe drop dynamics or movement behavior of drop in which the drop diameter size grouped based on current regime deputizing with Reynolds Number (Re) and to study mass transfer liquid-liquid extraction in packed column based on drop diameter size influenced by flow rate and packing type. Observation of drop behavior is done by using length square column transparent so that visually drop dynamics can be observed and recorded at every segment of column height using digital camera. This research will be done by varying packing type and flow rate of the dispersed phase and continuous phase to know behavior of drop. The research will be done by using water–MEK (methyl ethyl ketone)–n-hexane system. The result of this research for packing type of sphere and raschig ring show that more and more big dispersed phase flow rate and height from under side column (distributor), hence drop is more and more small with number of which more and more many. This caused significant increase on overall mass transfer coefficient.Keywords: drop distribution, sphere, raschig ring, drop diameter Abstrak Proses perpindahan massa ekstraksi cair-cair dalam kolom isian terjadi akibat adanya kontak antara fase kontinu dan fase dispersi yang dialirkan secara berlawanan. Berbagai macam ukuran dan jenis isian yang digunakan dalam kolom, menyebabkan luas permukaan kontak menjadi lebih besar dan waktu kontak makin lama sehingga terjadi peningkatan proses perpindahan massa. Penelitian ini bertujuan mengamati dinamika pergerakan tetesan dengan cara mengelompokkan ukuran diameter tetesan berdasarkan pada rezim aliran yang diwakilkan dengan Bilangan Reynold (Re) dan mempelajari perpindahan massa pada ekstrasi cair-cair dalam kolom isian yang didasarkan ukuran diameter tetesan yang dipengaruhi laju alir dan jenis isian. Pengamatan perilaku tetesan dilakukan dengan menggunakan kolom persegi panjang yang transparan sehingga secara visual dinamikanya dapat diamati dan direkam pada tiap segmen ketinggian kolom menggunakan kamera digital. Percobaan dilakukan dengan menggunakan sistem air-MEK (metil etil keton)-n-heksan. Hasil penelitian untuk jenis isian bola padat dan raschig ring menunjukkan bahwa makin besar laju alir fase dispersi dan ketinggian dari bagian bawah (distributor), maka tetesannya makin kecil dengan jumlah yang makin banyak. Hal ini menyebabkan kenaikan yang signifikan terhadap koefisien perpindahan massa keseluruhan.Kata kunci: distribusi tetesan, bola, raschig ring, diameter tetesan.

scholarly journals Reactive Zinc Extraction in MRDC Column; Case Study by Mathematical Modelling and Applying the Droplet Size Distribution with Forward Mixing Approach

2021 ◽  
Author(s):  
Benyamin Shakib ◽  
Rezvan Torkaman ◽  
Meisam Torab-Mostaedi ◽  
Mojtaba Saremi ◽  
Mehdi Asadollahzadeh
Keyword(s):  
Mathematical Modeling ◽  
Mass Transfer ◽  
Solvent Extraction ◽  
Mass Transfer Rate ◽  
Continuous Phase ◽  
Axial Dispersion ◽  
Extraction Column ◽  
Dispersed Phase ◽  
Rotor Speed ◽  
Zinc Extraction

Abstract In this survey, the reactive mass transfer data are determined for zinc extraction from chloride solution using D2EHPA in the MRDC extraction column. The numerical analysis for evaluating the column performance is applied to describe mass balance equations. Four mathematical models (backflow, forward mixing, plug flow, and axial dispersion) are investigated to compute the mass transfer coefficients of the dispersed phase. The solvent extraction experiments showed that the optimum zinc transport efficiency in rotor speed of 410 rpm in this column is equal to 98.85% and 99.85 for extraction and stripping stages, respectively. The model's achievement is compared with the solvent extraction data and a significant validity is obtained by coupling the forward mixing approach. The mathematical modeling expresses that the coefficients of axial dispersion and backflow based on the continuous phase increase by an increase in the rotor speed and inlet continuous phase rate. While these coefficients reduce at a higher inlet dispersed phase rate. The FMM method is preferred to predict the reactive mass transfer rate in the MRDC column due to the lowest relative deviation. The experimental study and mathematical modeling in this report provide beneficial information about the metallurgical industry to design solvent extraction equipment.

Phase Inversion in Two-Phase Liquid Systems

1992 ◽  
Vol 57 (7) ◽  
pp. 1419-1423
Author(s):  
Jindřich Weiss
Keyword(s):  
Interfacial Tension ◽  
Phase Inversion ◽  
Continuous Phase ◽  
Considerable Effect ◽  
Weak Dependence ◽  
Dispersed Phase ◽  
Two Phase ◽  
Liquid Systems ◽  
Phase Liquid

New data on critical holdups of dispersed phase were measured at which the phase inversion took place. The systems studied differed in the ratio of phase viscosities and interfacial tension. A weak dependence was found of critical holdups on the impeller revolutions and on the material contactor; on the contrary, a considerable effect of viscosity was found out as far as the viscosity of continuous phase exceeded that of dispersed phase.

Capillary pressure, osmotic pressure and bubble contact areas in foams

Soft Matter ◽  
2021 ◽  
Author(s):  
Reinhard Höhler ◽  
Jordan Seknagi ◽  
Andrew Kraynik
Keyword(s):  
Osmotic Pressure ◽  
Capillary Pressure ◽  
Continuous Phase ◽  
Dispersed Phase ◽  
Average Pressure ◽  
Contact Areas ◽  
The Difference

The capillary pressure of foams and emulsions is the difference between the average pressure in the dispersed phase and the pressure in the continuous phase.

Effect of Geometry on Droplet Generation in a Microfluidic T-Junction

2013 ◽  
Author(s):  
Katerina Loizou ◽  
Wim Thielemans ◽  
Buddhika N. Hewakandamby
Keyword(s):  
Aspect Ratio ◽  
Cross Section ◽  
Droplet Formation ◽  
Continuous Phase ◽  
Main Channel ◽  
Superficial Velocity ◽  
Droplet Generation ◽  
Dispersed Phase ◽  
Aspect Ratios ◽  
The Cross

The main aim of this study is to examine how the droplet formation in microfluidic T-junctions is influenced by the cross-section and aspect ratio of the microchannels. Several studies focusing on droplet formation in microfluidic devices have investigated the effect of geometry on droplet generation in terms of the ratio between the width of the main channel and the width of the side arm of the T-junction. However, the contribution of the aspect ratio and thus that of the cross-section on the mechanism of break up has not been examined thoroughly with most of the existing work performed in the squeezing regime. Two different microchannel geometries of varying aspect ratios are employed in an attempt to quantify the effect of the ratio between the width of the main channel and the height of the channel on droplet formation. As both height and width of microchannels affect the area on which shear stress acts deforming the dispersed phase fluid thread up to the limit of detaching a droplet, it is postulated that geometry and specifically cross-section of the main channel contribute on the droplet break-up mechanisms and should not be neglected. The above hypothesis is examined in detail, comparing the volume of generated microdroplets at constant flowrate ratios and superficial velocities of continuous phase in two microchannel systems of two different aspect ratios operating at dripping regime. High-speed imaging has been utilised to visualise and measure droplets formed at different flowrates corresponding to constant superficial velocities. Comparing volumes of generated droplets in the two geometries of area ratio near 1.5, a significant increase in volume is reported for the larger aspect ratio utilised, at all superficial velocities tested. As both superficial velocity of continuous phase and flowrate ratio are fixed, superficial velocity of dispersed phase varies. However this variation is not considered to be large enough to justify the significant increase in the droplet volume. Therefore it can be concluded that droplet generation is influenced by the aspect ratio and thus the cross-section of the main channel and its effect should not be depreciated. The paper will present supporting evidence in detail and a comparison of the findings with the existing theories which are mainly focused on the squeezing regime.

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