Interphase Surface Stability in Liquid-Liquid Membrane Contactors Based on Track-Etched Membranes

A promising solution for the implementation of extraction processes is liquid–liquid membrane contactors. The transfer of the target component from one immiscible liquid to another is carried out inside membrane pores. For the first time, highly asymmetric track-etched membranes made of polyethylene terephthalate (PET) of the same thickness but with different pore diameters (12.5–19 nm on one side and hundreds of nanometers on the other side) were studied in the liquid–liquid membrane contactor. For analysis of the liquid–liquid interface stability, two systems widely diverging in the interfacial tension value were used: water–pentanol and water–hexadecane. The interface stability was investigated depending on the following process parameters: the porous structure, the location of the asymmetric membrane in the contactor, the velocities of liquids, and the pressure drop between them. It was shown that the stability of the interface increases with decreasing pore size. Furthermore, it is preferable to supply the aqueous phase from the side of the asymmetric membrane with the larger pore size. The asymmetry of the porous structure of the membrane makes it possible to increase the range of pressure drop values between the phases by at least two times (from 5 to 10 kPa), which does not lead to mutual dispersion of the liquids. The liquid–liquid contactor based on the asymmetric track-etched membranes allows for the extraction of impurities from the organic phase into the aqueous phase by using a 1% solution of acetone in hexadecane as an example.

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Gas-liquid membrane contactors: Effects of polymer concentration and solvent type on pore size distribution

Journal of Membrane Science ◽

10.1016/j.memsci.2018.05.034 ◽

2018 ◽

Vol 563 ◽

pp. 813-819 ◽

Cited By ~ 2

Author(s):

Ashkan Zolfaghari ◽

Seyyed Abbas Mousavi ◽

Ramin Bozorgmehri Bozarjomehri ◽

Fatemeh Bakhtiari

Keyword(s):

Pore Size Distribution ◽

Pore Size ◽

Size Distribution ◽

Liquid Membrane ◽

Polymer Concentration ◽

Solvent Type ◽

Membrane Contactors

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A Comparison of Porous and Non-Porous Gas-Liquid Membrane Contactors for Gas Separation

Chemical Engineering Research and Design ◽

10.1205/026387697524182 ◽

1997 ◽

Vol 75 (7) ◽

pp. 685-692 ◽

Cited By ~ 39

Author(s):

H.B. Al-saffar ◽

B. Ozturk ◽

R. Hughes

Keyword(s):

Gas Separation ◽

Liquid Membrane ◽

Membrane Contactors

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Porous structure and pore size control of mesoporous carbons using a combination of a soft-templating method and a solvent evaporation technique

Colloids and Surfaces A Physicochemical and Engineering Aspects ◽

10.1016/j.colsurfa.2016.01.009 ◽

2016 ◽

Vol 494 ◽

pp. 180-185 ◽

Cited By ~ 5

Author(s):

Takahito Mitome ◽

Yuichiro Hirota ◽

Yoshiaki Uchida ◽

Norikazu Nishiyama

Keyword(s):

Porous Structure ◽

Pore Size ◽

Size Control ◽

Solvent Evaporation ◽

Mesoporous Carbons ◽

Templating Method ◽

Soft Templating ◽

Evaporation Technique ◽

Pore Size Control

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The adsorption characteristics and porous structure of bentonite adsorbents, determined from the adsorption isotherms of benzene vapor

Journal of the Serbian Chemical Society ◽

10.2298/jsc0402145b ◽

2004 ◽

Vol 69 (2) ◽

pp. 145-151 ◽

Cited By ~ 5

Author(s):

Snezana Brezovska ◽

Biljana Marina ◽

Biljana Panova ◽

Donco Burevski ◽

Vasa Bosevska ◽

...

Keyword(s):

Free Energy ◽

Porous Structure ◽

Pore Size ◽

Adsorption Isotherms ◽

Micropore Volume ◽

Benzene Vapor ◽

Free Energy Of Adsorption ◽

Volume Filling ◽

Activated Bentonite ◽

Characteristic Values

The adsorption of benzene vapor on natural and acid activated bentonites was treated by the theory of volume filling of micropores. The micropore volume and characteristic values of the free energy of adsorptionwere determined from the adsorption isotherms. The Dubinin?Radushkevish?Stoeckli and Dubinin?Astakhov equations were used for this purpose. The results showed that natural bentonite has a more homogeneous micropore structure than the acid activated ones. The characteristic values of the free energy of adsorption for the natural bentonite were higher than those of the acid activated bentonite. This is due to differences in its structure and the pore size.

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The Influence of Loop Heat Pipe Evaporator Porous Structure Parameters and Charge on Its Effectiveness for Ethanol and Water as Working Fluids

Materials ◽

10.3390/ma14227029 ◽

2021 ◽

Vol 14 (22) ◽

pp. 7029

Author(s):

Krzysztof Blauciak ◽

Pawel Szymanski ◽

Dariusz Mikielewicz

Keyword(s):

Porous Structure ◽

Pore Size ◽

Heat Pipe ◽

Capillary Pressure ◽

Pressure Difference ◽

Working Fluid ◽

Loop Heat Pipe ◽

Working Fluids ◽

Integral Characteristics ◽

Sintered Stainless Steel

This paper presents the results of experiments carried out on a specially designed experimental rig designed for the study of capillary pressure generated in the Loop Heat Pipe (LHP) evaporator. The commercially available porous structure made of sintered stainless steel constitutes the wick. Three different geometries of the porous wicks were tested, featuring the pore radius of 1, 3 and 7 µm. Ethanol and water as two different working fluids were tested at three different evaporator temperatures and three different installation charges. The paper firstly presents distributions of generated pressure in the LHP, indicating that the capillary pressure difference is generated in the porous structure. When installing with a wick that has a pore size of 1 μm and water as a working fluid, the pressure difference can reach up to 2.5 kPa at the installation charge of 65 mL. When installing with a wick that has a pore size of 1 μm and ethanol as a working fluid, the pressure difference can reach up to 2.1 kPa at the installation charge of 65 mL. The integral characteristics of the LHP were developed, namely, the mass flow rate vs. applied heat flux for both fluids. The results show that water offers larger pressure differences for developing the capillary pressure effect in the installation in comparison to ethanol. Additionally, this research presents the feasibility of manufacturing inexpensive LHPs with filter medium as a wick material and its influence on the LHP’s thermal performance.

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Hollow fiber gas–liquid membrane contactors for acid gas capture: A review

Journal of Hazardous Materials ◽

10.1016/j.jhazmat.2009.06.026 ◽

2009 ◽

Vol 171 (1-3) ◽

pp. 38-53 ◽

Cited By ~ 237

Author(s):

A. Mansourizadeh ◽

A.F. Ismail

Keyword(s):

Hollow Fiber ◽

Liquid Membrane ◽

Acid Gas ◽

Membrane Contactors

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Statistical Based Estimation of Biporous Evaporator Dryout

Volume 2: Heat Transfer Enhancement for Practical Applications; Heat and Mass Transfer in Fire and Combustion; Heat Transfer in Multiphase Systems; Heat and Mass Transfer in Biotechnology ◽

10.1115/ht2013-17704 ◽

2013 ◽

Author(s):

Sean Reilly ◽

Ivan Catton

Keyword(s):

Pressure Drop ◽

Pore Size Distribution ◽

Pore Size ◽

Capillary Pressure ◽

Size Distribution ◽

Numerical Estimate ◽

Effective Means ◽

Electronics Cooling ◽

Vapor Permeability ◽

Dry Out

Biporous wicks are an effective means for facilitating evaporation in heat pipes used for electronics cooling. They facilitate boiling within the wick by having two distinct size distributions of pores; the smaller pores provide high capillary pressure to pump liquid to the surface while the larger pores maintain high vapor permeability. The wicks investigated in this study were sintered copper biporous material. The authors previously presented a validated statistical model, based on work by Kovalev, which could predict the performance of biporous wicks tested at UCLA with reasonable accuracy [1]. Using this model, the author was able to gain new insight into the effect that the numerical estimate of liquid saturation of the wick has on dry out. The pore size distribution allows the determination of the capillary pressure available inside the wick and the Kovalev model provides the required pressure drop to supply liquid water to the heater surface. This led to a method of predicting dry out by comparing the capillary pressure in the wick to the required pressure drop from the model to estimate when the wick was dried out. When the required pressure drop determined by code exceeds the peak effective capillary pressure provided by the wick, the large pores of the wick are considered to be dry. These values are correlated to the input heat flux to determine what at what input power the wick begins to dry out. While the wick will not fail in this mode, the overall heat transfer coefficient will have peaked. In this work, this method of determining dry out will be validated against wicks tested at UCLA by comparing the input powers at which this dry out phenomenon occurs. Accurate predictions of dry out and the role of the pore size distribution are critical in developing methods to delay dry out of biporous wicks. By comparing the relative dry out points of various wick geometries to each other, augmented wick geometries can be suggested for future work. This modeling tool can lay the foundation for future tailoring of biporous evaporator wicks to specific tasks.

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