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Continuous separation, with microfluidics, of the components of a ternary mixture: from vacuum to purge gas pervaporation

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Iwona Ziemecka at Université Libre de Bruxelles
Iwona Ziemecka
Benoit Haut at Université Libre de Bruxelles
Benoit Haut
Benoit Scheid at Université Libre de Bruxelles
Benoit Scheid
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The general objective of this paper is to investigate the separation, with microfluidics, of the components of a ternary mixture, when using vacuum or purge gas pervaporation. The ternary mixture considered is a mixture of methanol (MeOH), water (H2O) and hydrogen peroxide (H2O2). In a previous work (Ziemecka in Lab Chip 15:504–511, 2015), we presented the proof of concept of a microfluidic device, which was able to partially separate MeOH from the other components of such a mixture, by using vacuum pervaporation. Here, our goal is to optimize the operation of this device, by considering vacuum pervaporation, but also purge gas pervaporation. First, we provide a mathematical model of the device. This model is used to discuss the influence of the operating parameters on the device operation. To apply this model to the considered mixture, we determined the MeOH and H2O permeability coefficients of PDMS membranes prepared from different concentrations of the curing agent. The model is then successfully compared to experimental data. The model and the experiments show that high efficiencies can be reached for both vacuum and purge gas pervaporation, provided a fine-tuning of the operating parameters. For instance, a good efficiency of the vacuum pervaporation is reached at high temperature and low pressure. For purge gas pervaporation, it is reached for low temperature and high pressure.
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Microfluid Nanofluid (2017) 21:84
DOI 10.1007/s10404-017-1915-6
RESEARCH PAPER
Continuous separation, with microfluidics, of the components of a
ternary mixture: from vacuum to purge gas pervaporation
Iwona Ziemecka1 · Benoît Haut1 · Benoit Scheid1
Received: 9 January 2017 / Accepted: 4 April 2017 / Published online: 18 April 2017
© Springer-Verlag Berlin Heidelberg 2017
high temperature and low pressure. For purge gas pervapo-
ration, it is reached for low temperature and high pressure.
Keywords Hydrogen peroxide · Microfluidics · Ternary
mixture · Separation · Membrane · Vacuum pervaporation ·
Purge gas pervaporation
1 Introduction
Hydrogen peroxide (H2O2) has both reducing and oxidizing
properties and is used in a wide spectrum of applications
ranging from cosmetic products to military technology.
Hydrogen peroxide is widely used in industry for bleaching
purposes (paper, tissues) and water treatment. It can also
be used as a source of green energy because when H2O2
is used as a fuel, it decomposes into water and oxygen, i.e.
products with no environmental impact. It is produced in
very high concentration (up to 70 wt% in water) through
the anthraquinone process. The problems of that way of
preparation are effective quinone recycling and formation
of by-products, which have to be disposed.
In recent years, a new high-yield process has been
developed (Bloomfield and Dhaese 2013) based on an
optimized distribution of anthraquinone isomers for the
production of solutions with 100% H2O2 content. This
new process led to the construction of mega-scale plants
able to produce massive amount of H2O2 per year, which
should direct towards reductions in production costs.
Nevertheless, another issue needing to be addressed lies
on the fact that the manufacture of concentrated H2O2
cannot be performed where it is meant to be used. Indeed,
the H2O2 production plants require specific authoriza-
tion and are usually far from urban centres. Therefore,
in most cases, dilution before transportation is needed.
Abstract The general objective of this paper is to investi-
gate the separation, with microfluidics, of the components
of a ternary mixture, when using vacuum or purge gas
pervaporation. The ternary mixture considered is a mix-
ture of methanol (MeOH), water (H2O) and hydrogen per-
oxide (H2O2). In a previous work (Ziemecka in Lab Chip
15:504–511, 2015), we presented the proof of concept of
a microfluidic device, which was able to partially sepa-
rate MeOH from the other components of such a mixture,
by using vacuum pervaporation. Here, our goal is to opti-
mize the operation of this device, by considering vacuum
pervaporation, but also purge gas pervaporation. First, we
provide a mathematical model of the device. This model is
used to discuss the influence of the operating parameters on
the device operation. To apply this model to the considered
mixture, we determined the MeOH and H2O permeability
coefficients of PDMS membranes prepared from different
concentrations of the curing agent. The model is then suc-
cessfully compared to experimental data. The model and
the experiments show that high efficiencies can be reached
for both vacuum and purge gas pervaporation, provided
a fine-tuning of the operating parameters. For instance, a
good efficiency of the vacuum pervaporation is reached at
* Iwona Ziemecka
Iwona.Ziemecka@ulb.ac.be
Benoît Haut
bhaut@ulb.ac.be
Benoit Scheid
bscheid@ulb.ac.be
1 TIPs - Fluid Physics, Ecole polytechnique de Bruxelles,
Université libre de Bruxelles, C.P. 165/67, avenue F.D.
Roosevelt 50, 1050 Brussels, Belgium
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
... As a result of the improvements of mass transport processes in confined systems, pervaporation has been succesfully translated to microfluidic settings [37][38][39][40]. PDMS membranes ranging between a few tens or hundreads of micrometers have been integrated and used to remove methanol [37,40], or acetone [38] from water solutions. ...
... As a result of the improvements of mass transport processes in confined systems, pervaporation has been succesfully translated to microfluidic settings [37][38][39][40]. PDMS membranes ranging between a few tens or hundreads of micrometers have been integrated and used to remove methanol [37,40], or acetone [38] from water solutions. Methanol amount was decreased in the liquid phase by a factor of four at 85°C [37] as well as acetone removal efficiency of 81% was achieved for 3 min of residence time at room temperature [38]. ...
... Methanol amount was decreased in the liquid phase by a factor of four at 85°C [37] as well as acetone removal efficiency of 81% was achieved for 3 min of residence time at room temperature [38]. The efficiency of the pervaporation process has been related to operating conditions such as the geometry of the chip (length and width of the channels), the thickness of the membrane, the flow rate of the inlet mixture and the permeability of the membrane [40]. ...
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... • Continuous separation of ternary mixtures by microfluidics • Recovery of organic components from wastewater [69,70] Condensable carrier gas purging PV ...
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