Subscriber access provided by WEBSTER UNIV
New Concepts at the Interface: Novel Viewpoints and Interpretations, Theory and Computations
Chemical reaction-driven spreading of organic extractant on gas-water interface: Insight into controllable formation of gas bubble-supported organic extractant liquid membrane jie liu, Kun Huang, Wenqian Liu, and Huizhou Liu Langmuir, Just Accepted Manuscript • DOI: 10.1021/acs.langmuir.8b03954 • Publication Date (Web): 18 Feb 2019 Downloaded from http://pubs.acs.org on February 21, 2019
Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.
is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.
Page 1 of 36 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
Langmuir
1
Chemical reaction-driven spreading of organic extractant on
2
gas-water interface: Insight into controllable formation of gas
3
bubble-supported organic extractant liquid membrane
4 5
Jie Liua, Kun Huangb,c*, Wenqian Liuc, Huizhou Liuc
6 7
a. School of Environmental and Municipal Engineering, Qingdao University of
8
Technology, Qingdao 266100, P.R. China
9
b. School of Metallurgical and Ecological Engineering, University of Science &
10
Technology Beijing, Beijing 100083, P.R. China
11
c. CAS Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and
12
Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266100, P.R. China
13 14
* To whom correspondence should be addressed:
15
Prof. Dr. Kun HUANG
16
Full postal address: School of Metallurgical and Ecological Engineering, University
17
of Science & Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing
18
100083, P. R. China
19
E-mail:
[email protected] 20
TEL:
86-10-62332926;
FAX:
1
ACS Paragon Plus Environment
86-10-62332926
Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
1
ABSTRACT
2
Extraction and recovery of low-concentration valuable metals from various
3
complex aqueous solutions or industrial waste waters have attract extensive interests
4
in recent years. In our previous works, we suggested a novel technique called
5
bubbling organic liquid membrane extraction by spreading and covering an organic
6
extractant with extremely small volume on the surface of gas bubbles to form a layer
7
of gas bubble-supported organic liquid membrane for selective extraction and
8
enrichment of low-concentration targets from dilute aqueous solutions. It was found
9
that, for successfully performing the bubbling organic liquid membrane extraction, a
10
prerequisite is how to control the formation of stable organic liquid membrane
11
covered on the surface of gas bubbles. However, once the organic extractant starting
12
to spread on the surface of gas bubbles, the extraction chemical reaction at the
13
interface between organic extractant liquid membrane and rare-earth aqueous solution
14
will happen. In the present work, the spreading behavior of organic extractant P507
15
on the surface of rare-earth aqueous solutions were investigated, and was compared
16
with the behaviors on the surface of deionized water. It was revealed that the
17
spreading of organic extractant P507 on the surface of aqueous solutions containing
18
rare-earth ions was accelerated due to the occurrence of the chemical reactions at the
19
gas-water interface. The difference in spreading rate of organic extractant P507 liquid
20
droplets respectively on the surface of deionized water and on that of Er(III) aqueous
21
solutions with the increase in P507 concentration, the saponification degrees of P507
22
extractant and the pre-loading amount of Er(III) in P507 extractant revealed that the 2
ACS Paragon Plus Environment
Page 2 of 36
Page 3 of 36 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
Langmuir
1
chemical reaction at the interface between the spreading P507 thin liquid membrane
2
and Er(III) aqueous solution would result in the Marangoni convection along the
3
interface, which is favor of overcoming the resistance from the viscous force when
4
surface tension gradient replaces the gravity as a dominant driving force for the
5
spreading. The present work provides an experimental foundation towards
6
understanding the effect of the interfacial chemical reaction on the spreading behavior
7
of organic oil droplet on the gas-water interface.
8
of our suggested new technique of bubbling organic liquid membrane extraction, and
9
to achieve a controllable generation of stable gas bubble-supported organic liquid
10
It is beneficial for the development
membrane for performing solvent extraction at large aqueous-to-oil phase ratios.
11 12 13
Keywords: Spreading and Wetting; Organic extractant; Solvent extraction; Bubbling
14
organic liquid membrane extraction; Rare earths
15 16
3
ACS Paragon Plus Environment
Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
1
INTRODUCTION
2
Nowadays, extraction and recovery of low-concentration valuable metals from
3
various complex aqueous solutions or industrial waste waters have attracted extensive
4
research interests.1 In our previous works, we suggested a novel technique called
5
bubbling organic liquid membrane extraction by spreading and covering a layer of
6
organic extractant with extremely small volume on the surface of gas bubbles to form
7
a gas bubble-supported organic liquid membrane for selective extraction and
8
enrichment of low-concentration targets from dilute aqueous solutions.2 Experimental
9
results demonstrated that the suggested new technique exhibited a great potential in
10
promoting the development of traditional oil-water two-phase solvent extraction to
11
treat the low-concentration diluted aqueous solutions economically. The dispersed gas
12
bubbles covered with organic extractant ascended in the extraction tower and
13
contacted counter-currently with the aqueous phase. Under the action of shearing
14
force of counter-current water phase, the renewal of the oil-water interface of the
15
organic thin membrane layer on the surface of gas bubbles was very fast, so that the
16
target metal ions with very low concentrations in the large volume of aqueous
17
solutions could be quickly captured and enriched into the organic liquid membrane
18
layer on the surface of gas bubbles at large aqueous-to-oil phase ratios (generally
19
above 600:1).3
20
However, it was found that, for successfully performing the bubbling organic
21
liquid membrane extraction, a prerequisite was how to control the formation of stable
22
organic liquid membrane covered on the surface of gas bubbles.4 When the gas was 4
ACS Paragon Plus Environment
Page 4 of 36
Page 5 of 36 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
Langmuir
1
bubbled into the aqueous solutions through the internal gas needles of the injector, the
2
organic extractant passed through the annular gaps between the internal gas needles
3
and the external organic needles, and then met with the gas bubbles on the top end of
4
the gas needles, so that the organic extractant could be dispersed and spread on the
5
surface of gas bubbles, due to its surface activity. If the pumping speed of the gas and
6
the organic phase were kept at a certain value, and if the materials used for making
7
the internal gas and external organic needles of the injector in bubbling organic liquid
8
membrane extractor were carefully designed, the formation of stable gas
9
bubble-supported organic liquid membrane from the submerged orifice of the
10
injectors in the large-phase-ratio extractor was closely related to the wettability and
11
spreading behavior of organic extractant on the surface of gas bubbles.5 Therefore, in
12
order to achieve a controllable generation of stable gas bubble-supported organic
13
liquid membrane, it is necessary to understand what factors might bring obvious
14
influence on the spreading behavior of organic extractant and which one is the most
15
crucial.
16
Investigations in the literatures about the spreading behavior of organic liquid
17
droplets on the gas-water interface have been extensively reported.6-8 Early,
18
Robinson and Woods suggested that the spreading free energy, E, could be used to
19
judge whether an organic liquid droplet could enter the air-water interface: 9
E aw ow ao
20
(1)
21
where,
aw
is the surface tension of water.
22
liquid film.
ow
is the interface tension between organic liquid film and water. When
ao
is the surface tension of organic
5
ACS Paragon Plus Environment
Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
Page 6 of 36
1
E >0, it was thought that the organic liquid droplet could enter into the interface
2
between air and water, and to form a lens or spread to form a thin organic liquid film.
3
Since that, Harkins and Feldman studied the wetting and spreading behavior of an
4
organic liquid drop after entering the interface between air and water.10 Their works
5
indicated that whether or not the organic liquid droplet could spread on the air-water
6
interface was closely depended on the spreading coefficient, S :
7
s aw ow ao
(2)
8
When S 0, the spreading of organic liquid droplet on
10
the air-water interface was possible and finally an organic lens or a thin organic liquid
11
film could be obtained on the surface of water.
12
Based on those pioneered works, the researchers combined together the free
13
energy, E, and the spreading coefficient, S, to further describe the spreading behavior
14
of organic liquid droplet on the air-water interface.11 It was found that there were
15
three types of spreading behavior of organic droplet on the air-water interface. When
16
E 98%, purchased from Xiamen Pioneer Technology Co. Ltd., was
14
used as the organic extractant. The 260# sulfonated kerosene, purchased from China
15
Petrochemical Corporation (Sinopec Group), was used as the diluent. The content of
16
various aromatic hydrocarbons in the 260# sulfonated kerosene was below 1%. The
17
stock organic solutions of P507 in kerosene with different molar concentrations of
18
P507 were prepared by respectively mixing a certain amount of P507 with kerosene at
19
different volume ratios. All of the organics were used as received, without further
20
purification. Analytical-grade (purity > 99%) of sodium hydroxide, purchased from
21
Sinopharm Chemical Reagent Co., Ltd, was dissolved into deionized water to prepare
22
3 mol/L NaOH aqueous solutions for saponification of P507 in kerosene solutions. 9
ACS Paragon Plus Environment
Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
1
The desired saponification degrees of P507 in kerosene solutions were obtained
2
according to the procedures as mentioned in previous literatures.31 The stock aqueous
3
solutions containing a certain amount of Erbium (Er) were prepared by firstly
4
dissolving analytical grade (purity > 99%) of Er2O3 (purchased from Ganzhou
5
Shunyuan Rare Earth Material Co., Ltd) using 37 wt% concentrated HCl aqueous
6
solutions, and then boiled the aqueous solutions to drive out the HCl, and then diluted
7
to the desired concentrations using deionized water. The pre-loaded P507 organic
8
solution containing a certain amount of Erbium were prepared by mixing the
9
pre-saponified P507 organic solution with the stock aqueous solutions containing a
10
known quantity of Erbium for 30 min at room temperature. After oil and aqueous
11
phase separation, the concentrations of Erbium in the loaded organic phase were
12
determined.
13
The other chemicals were of analytical grade.
14 15
Experimental Set-up.
16
Experimental set-up consisted of an injection pump (TSD01-01, Baoding
17
Leadfluid, Ltd. Co., China), a backlight (FJI-AS150150-W, Rocke TECH. Ltd. Co.,
18
China), a high-speed video camera (CP80-3-M-540, Optronis, Germany) and a high-
19
speed image recording processing system (AcutEye V3.0, Rocke TECH. Ltd. Co.,
20
China), as shown in Fig. 1.
21
10
ACS Paragon Plus Environment
Page 10 of 36
Page 11 of 36 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
Langmuir
1 2
Figure 1. Experimental set-up
3 4
Experimental supporting liquids for spreading of P507 organic solutions were
5
respectively the deionized water, or the Er(III) aqueous solutions prepared from its
6
original stock solution as mentioned in section 2.1. The concentrations of Er(III) in
7
the supporting aqueous solution were 30 mg/L, and the pH of the supporting Er(III)
8
aqueous solutions were 5.4. The aim to adjust the pH of the supporting Er(III)
9
aqueous solutions to 5.4 is for the comparison with the spreading on the surface of the
10
deionized water. The supporting liquids were previously poured into a Petri dish with
11
a diameter of 10 cm and a depth of 1.8 cm. The depth of Er(III) aqueous solutions or
12
deionized water in the petri dish was 1.0 cm. An injection pump was used to generate
13
stable organic droplets with a fixed volume of 5μL for per droplet. In order to
14
minimize the impact of falling velocity of the organic droplet on its spreading on the
15
surface of the tested supporting aqueous solution, the syringe needle of the injection
16
pump was bent to 90 degree, and the distance between the needle tip and the surface 11
ACS Paragon Plus Environment
Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
1
of the tested supporting aqueous solution in the petri dish was pre-set as 1~2 mm. The
2
high-speed video camera, equipped with Nikon micro-lens (50 mm, 1: 1.4 fixed focus
3
lens), was fixed on a tripod and connected to the high-speed image recording
4
processing system. The micro-lens of camera was located above the tested surface,
5
and the spreading behavior of organic droplets on the surface of the tested supporting
6
aqueous solution could be recorded by the high-speed image recording processing
7
system. The backlight, fixed on the shelf and kept at an angle of 30 to 45 degree with
8
the micro-lens of the camera, was used to provide a cold light source for different
9
brightness. The spreading images obtained from the high-speed camera were
10
processed by the software Image Pro Plus 6.0.
11
The view-field of the high-speed video camera was 13.57 mm*13.68 mm. The
12
maximum resolution of the camera was 1696*1710 dpi. The exposure time was 2μs.
13
The image acquisition frame of the camera was 543 fps, and the storage frame rate
14
was 25 fps.
15
Similar experimental procedures could be referred to other works .32
16 17
Analysis.
18
The concentrations of Er(III) in the pre-loaded P507 organic phases were
19
determined by an Agilent 7900 ICP-MS system (Agilent Technologies, USA). The
20
saponification degrees of P507 in organic phases were determined by the acid value
21
titration processes using 0.1 mol/L NaOH aqueous solutions. The interfacial viscosity
22
and elasticity modulus of the sample organic droplets with different P507 12
ACS Paragon Plus Environment
Page 12 of 36
Page 13 of 36 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
Langmuir
1
concentrations, the saponification degrees of P507 and pre-loading concentrations of
2
Er(III) were measured by the oscillating barrier method performed using a Kruss
3
K100 Mk2 tensiometer, and the surface and interface tensions of the sample organic
4
solutions respectively on the surface of deionized water and that of Er(III) aqueous
5
solutions were measured by the Wilhelmy plate method. Detailed information about
6
the apparatus and the experimental procedures for the determination of the interfacial
7
viscosity and elasticity modulus, and the surface and interface tension could be
8
referred to previous literatures.33-35 The viscosity of the sample organic solutions were
9
recorded by using an Ubbohde's viscosimeter (NDJ-8S, Shanghai, China).
10 11
Data processing.
12
The time-dependent changes in spreading area of the organic droplets with
13
different P507 concentrations, the saponification degrees of P507 extractant and the
14
pre-loading amount of Er(III) in organic solution were recorded respectively on the
15
surface of deionized water and on the surface of Er(III) aqueous solutions, as shown
16
in Fig. S1 to S6 in Supporting Information.
17
In order to modelling the spreading process of P507 organic droplets on the
18
surface of different tested supporting aqueous solutions, the time-dependent changes
19
in the spreading areas of P507 organic droplets with the increase of P507
20
concentrations, the saponification degrees of P507 extractant and the pre-loading
21
amount of Er(III) in organic solution were curve-fitted by using the classical
22
spreading area- time model, as shown in equ.(3), which was demonstrated reasonable 13
ACS Paragon Plus Environment
Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
Page 14 of 36
1
in most cases for the description of the spreading kinetics of organic oil droplets on
2
the surface of water in previous literatures 36-38: A= kt n
3
(3)
4
In which, A is the spreading area of P507 organic droplets on the surface of the
5
tested supporting aqueous solutions. t is the spreading time. n is an empirical constant.
6
k is the empirical spreading coefficient. All the fitting equations were listed in Table
7
S1 to S6 in Supporting Information. The spreading rate of P507 organic droplets can
8
be expressed as:
dA nkt n 1 dt
9
(4)
10 11
RESULTS
12
The effect of P507 concentrations.
13
Fig. 2 depicts the time-dependent changes in spreading rate of the P507 organic
14
droplets with the increase in the concentrations of P507 extractant, respectively on the
15
surface of deionized water (Fig.2a) and on the surface of Er(III) aqueous solutions
16
(Fig.2b).
17 18
14
ACS Paragon Plus Environment
Page 15 of 36 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
Langmuir
1 2
Figure 2. (a) The time-dependent changes in spreading rate of P507 organic droplet on the surface
3
of deionized water with the increase in P507 concentrations. (b) The time-dependent changes in
4
spreading rate of P507 organic droplet on the surface of Er(III) aqueous solutions with the
5
increase in P507 concentrations.
6
(The saponification degrees of P507 in the organic phases were 5%. The concentration of
7
pre-loaded Er(III) in P507 organic phases were 0 g/L. The concentrations of Er(III) in aqueous
8
solution were 30 mg/L, and the pH of the Er(III) aqueous solutions were 5.4. )
9 10
As can be seen in Fig.2, both the spreading rates of P507 organic droplets on the
11
surface of deionized water and on that of Er(III) aqueous solutions decreased quickly
12
at initial time, and the spreading rates of P507 organic droplets decreased obviously
13
with the increase of P507 concentrations. However, the spreading rates of P507
14
organic droplets containing the same concentrations of P507 on the surface of the
15
aqueous solutions of Er(III) ions was larger than that on the surface of deionized
16
water at a certain time.
17
The change in the spreading rates can be divided as two typical stages: an initial
18
fast-speed decreasing of the spreading rates with the time, and then followed a 15
ACS Paragon Plus Environment
Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
1
slow-speed spreading stage. Here, for convenience of discussion, the so-called
2
slow-speed spreading stage is defined as that in which the change in the spreading
3
rates with the time is very slowly or even not changed any more. Comparing the
4
spreading process of P507 organic droplets on the surface of deionized water and on
5
that of Er(III) aqueous solutions, the change in the transition points of the spreading
6
rates from the initial fast-speed decreasing stage to the following slow-speed
7
spreading with the increase of the P507 concentrations are depicted in the Fig. 3.
8
9 10
Figure 3. (a) The change in the transition points of the spreading rates of P507 organic droplet on
11
the surface of deionized water with increasing the P507 concentrations. (b) The change in the
12
transition points of the spreading rates of P507 organic droplet on the surface of Er(III) aqueous
13
solutions with increasing the P507 concentrations.
14
(The saponification degrees of P507 in the organic phases were 5%. The concentration of
15
pre-loaded Er(III) in P507 organic phases were 0 g/L. The concentrations of Er(III) in aqueous
16
solution were 30 mg/L, and the pH of the Er(III) aqueous solutions were 5.4.)
17 18
The transition points of the spreading rates from the initial fast-speed decreasing 16
ACS Paragon Plus Environment
Page 16 of 36
Page 17 of 36 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
Langmuir
1
to the following slow-speed spreading are defined as the intersections of the two
2
straight lines, respectively corresponding to the linear fitting of those points in the
3
initial fast-speed decreasing stage and those in the final slow-speed decreasing stage
4
of the spreading rate-time curve. (See Fig.S7 in Supporting Information for how to
5
obtain the linear fitting of the two straight lines. The intersections of the two straight
6
lines are depicted as the O points.) The time corresponding to the O point is defined
7
as the time To for the transition point of the spreading rates. (See Fig.S7 in Supporting
8
Information for how to obtain the time To.)
9
As depicted in Fig. 3, the time To for the transition points of the spreading rates
10
decreased not only with the increase of P507 concentration, but also was linearly
11
negatively correlated with the concentration of P507 in the organic droplet, whether
12
on the surface of deionized water or on that of the Er(III) aqueous solutions. As for
13
the spreading of oil droplets with the same P507 concentrations, the To values for the
14
transition points of the spreading rates on the surface of deionized water were always
15
shorter than that on the surface of the Er(III) aqueous solutions. It means that, if an
16
extraction reaction occurred with the spreading of the P507 organic droplet, it might
17
result in the time to reach the transition points of the spreading rates increased
18
appreciably.
19 20
The effect of the saponification degrees of P507 extractant.
21
Fig. 4(a) and 5(a) depict the time-dependent changes in spreading rates of the
22
organic droplets with the increase in the saponification degrees of P507 extractant, 17
ACS Paragon Plus Environment
Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
1
respectively on the surface of deionized water and on the surface of Er(III) aqueous
2
solutions.
3
4 5
Figure 4. (a) The time-dependent changes in spreading rates of P507 organic droplet on the
6
surface of deionized water with increasing the saponification degrees of P507. (b) The change in
7
the transition points of the spreading rates of P507 organic droplet on the surface of deionized
8
water with increasing the saponification degrees of P507.
9
(The P507 concentrations in the organic phase were 1.5 mol/L. The concentration of pre-loaded
10
Er(III) in P507 organic phase were 0 g/L.)
11
12 13
Figure 5. (a) The time-dependent changes in spreading rates of P507 organic droplet on the 18
ACS Paragon Plus Environment
Page 18 of 36
Page 19 of 36 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
Langmuir
1
surface of Er(III) aqueous solutions with increasing the saponification degrees of P507. (b) The
2
change in the transition points of the spreading rates of P507 organic droplet on the surface of
3
Er(III) aqueous solutions with increasing the saponification degrees of P507.
4
(The P507 concentrations in the organic phase were 1.5 mol/L. The concentration of pre-loaded
5
Er(III) in P507 organic phase were 0 g/L. The concentrations of Er(III) in aqueous solution were
6
30 mg/L, and the pH of the Er(III) aqueous solutions were 5.4.)
7 8
As can be seen in Fig. 4(a) and Fig. 5(a), the changing trend of the spreading
9
rates with the increase in the saponification degrees of P507 organic droplets on the
10
surface of deionized water are similar with that on the surface of Er(III) aqueous
11
solutions. Within the initial 0.4 seconds, the spreading rates decreased appreciably,
12
then both of them reached a stable spreading at slow speed. In addition, both the
13
spreading rates of P507 organic droplets on the surface of deionized water and on that
14
of Er(III) aqueous solutions decreased with the increase in the P507 saponification
15
degrees. Comparing to the spreading on the surface of deionized water, the spreading
16
rates on the surface of Er(III) aqueous solutions were more quicker, even the
17
saponification degrees of P507 were the same. The curve of the spreading of P507
18
sample without saponification treatment is located within the range of saponification
19
degrees between 5% to 8%. The deviation of the spreading from the changing trend of
20
other samples with increasing saponification degrees might be attributed to a quick
21
decrease in the pH values of the supporting liquids, due to the ionization and release
22
out of hydrogen ions from the active groups in P507 molecules in the aqueous 19
ACS Paragon Plus Environment
Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
1
solutions under neutral pHs5, 39. Therefore, the resistance for the spreading of P507
2
organic solutions increased.
3
Fig. 4(b) and 5(b) give the change in the time To for the transition points of the
4
spreading rates from a rapid decrease to a slow-speed spreading with increasing the
5
saponification degrees of P507. Notably, the change in To was negatively correlated
6
with the saponification degrees of P507, whether the spreading was occurred on the
7
surface of deionized water or on that of Er(III) aqueous solutions. To became shorter
8
with increasing the P507 saponification degrees. However, the time To for the
9
transition points of the spreading on the surface of Er(III) aqueous solutions were
10
longer than that on the surface of deionized water.
11 12
The effect of the pre-loading amount of rare earths in organic phase.
13
Fig. 6(a) and 7(a) respectively depict the time-dependent changes in spreading
14
rates of the organic droplets with the increase in the pre-loading amount of Er(III) in
15
organic phase, respectively on the surface of deionized water and on the surface of
16
Er(III) aqueous solutions.
17
20
ACS Paragon Plus Environment
Page 20 of 36
Page 21 of 36 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
Langmuir
1 2
Figure 6. (a) The time-dependent changes in spreading rates of P507 organic droplet on the
3
surface of deionized water with increasing the pre-loaded concentrations of Er(III) in P507
4
extractant. (b) The change in the transition points of the spreading rates of P507 organic droplet on
5
the surface of deionized water with increasing the pre-loaded concentrations of Er(III) in P507
6
extractant .
7
(The P507 concentrations in the organic phases were 1.5 mol/L. The saponification degrees of
8
P507 in the organic phases were 5%.)
9
10 11
Figure 7. (a) The time-dependent changes in spreading rates of P507 organic droplet on the
12
surface of Er(III) aqueous solutions with increasing the pre-loaded concentrations of Er(III) in
13
P507 extractant. (b) The change in the transition points of the spreading rates of P507 organic 21
ACS Paragon Plus Environment
Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
1
droplet on the surface of Er(III) aqueous solutions with increasing the pre-loaded concentrations
2
of Er(III) in P507 extractant.
3
(The P507 concentrations in the organic phase were 1.5 mol/L. The saponification degrees of
4
P507 in the organic phases were 5%. The concentrations of Er(III) in aqueous solution were 30
5
mg/L, and the pH of the Er(III) aqueous solutions were 5.4.)
6 7
As can be seen in the Fig. 6(a) and Fig. 7(a), both the rates of the spreading of
8
P507 organic droplets on the surface of deionized water and on that of Er(III)
9
aqueous solutions decrease significantly with the time expanding, and then reaches a
10
slow spreading rate. The spreading rates of P507 organic droplets decreased with the
11
increase in the pre-loaded Erbium concentrations in the organic phases. However,
12
comparing to the changes in spreading rates on the surface of deionized water, the
13
change in spreading rates on the surface of Er(III) aqueous solutions were more
14
quicker, if the pre-loaded concentrations of Er(III) in P507 extractant were the same.
15
Fig. 6(b) and 7(b) depict the change in the time To for the transition points of the
16
spreading rates with increasing the pre-loaded concentrations of Er(III) in P507
17
extractant. Obviously, the change in To was negatively correlated with the pre-loading
18
amount of Er(III) in P507 organic droplets. The time To decreased with the increase of
19
the pre-loading Er(III) concentration in P507 organic droplets. However, all of the To
20
for the transition points of the spreading on the surface of Er(III) aqueous solutions
21
were longer than that on the surface of deionized water.
22 22
ACS Paragon Plus Environment
Page 22 of 36
Page 23 of 36 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
Langmuir
1
DISCUSSION
2
Previous experimental results indicated that the spreading rates decreased
3
quickly before the time To, and then reached a stable slow-speed spreading after To.
4
At the beginning of spreading, the gravity force is the dominant driving force to
5
induce the spreading. The organic droplets must overcome the deformation resistance
6
and the interfacial friction of the substrate liquid to spread and then gradually form a
7
thin oil film on the surface of water.40 In this stage, the inertia force is initially a
8
predominant resisting force, and then the viscous drag gradually replaces the inertia to
9
become a main retarding force. The later would become more and more obvious with
10
the increase of the spreading area of the organic droplet.15 Therefore, the spreading
11
rates of organic droplets decreased quickly at first and then slow down. The spreading
12
of the organic droplet results in the deformation of the organic droplet quickly from a
13
sphere to a flat organic lens on the supporting fluid.41
14
After the time T0, the organic lens spread further, and finally a thin precursor oil
15
film, even a monolayer, formed on the surface of the supporting substrate aqueous
16
solutions. In this stage, the surface tension gradient gradually replaces the gravity to
17
become the dominant driving force for spreading, although the viscous force is still a
18
main resisting force. The spreading rates of P507 organic droplet depended mainly on
19
the wettability of P507 oil membrane on the surface of the supporting substrate
20
aqueous solutions. Therefore, the spreading rates of organic droplets would not
21
change any more and reached a stable spreading rate.
22
As for the reasons why the spreading rates decreased with the increase of P507 23
ACS Paragon Plus Environment
Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
1
concentration, the saponification degree of P507 extractant and the pre-loaded Erbium
2
concentration, we thought it might be attribute to the change in the rheological
3
characteristics of P507 organic liquid membrane spreading on the surface of the
4
supporting substrate aqueous solutions.42 During the process of spreading, the ratios
5
of the viscosity to elasticity of P507 organic droplets reflect the damping capacity of
6
the droplets spreading on the surface of the supporting substrate aqueous
7
solutions.43,44 Figure 8 depicts the changes in the ratios of viscosity to elasticity of
8
P507 organic droplets with the increase in the concentration of P507, the
9
saponification degree of P507 extractant and the pre-loaded Erbium concentration.
10 11
Figure 8. The changes in the ratios of viscosity to elasticity of P507 organic droplets with (a) the
12
concentration of P507, (b) the saponification degree of P507 extractant, and (c) the pre-loaded
13
Erbium concentration in the organic phase. 24
ACS Paragon Plus Environment
Page 24 of 36
Page 25 of 36 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
Langmuir
1 2
As can be seen in the Fig. 8, the ratios of viscosity to elasticity (See Table S7 to
3
S9 in Supporting Information for how to calculate the ratios of viscosity to elasticity)
4
of P507 organic droplets increased with increasing the concentration of P507, the
5
saponification degree of P507 extractant, and the pre-loaded Erbium concentration in
6
the organic phase. It means that the damping capacity of P507 organic droplets
7
spreading on the surface of the supporting substrate aqueous solutions increased. The
8
increasing in damping capacity of organic droplets would lead to the increase in the
9
frictional resistance between the P507 organic liquid membrane and the supporting
10
substrate aqueous solutions.45 Therefore, the spreading rates of P507 organic droplets
11
decreased.
12
Experimental results indicated that the time To would become shorter with the
13
increase in P507 concentration, the saponification degree of P507 extractant and the
14
pre-loaded Erbium concentration. It might be attributed to the increase in viscosity of
15
P507 droplet with the increase of above three factors (The change in the viscosities of
16
the organic phases with the increase in P507 concentration, the saponification degree
17
of P507 extractant and the pre-loaded Erbium concentration are listed in Table S10 to
18
S12 in Supporting Information). The viscous force is a main resisting force before
19
time To, therefore, the increase in the viscosity of P507 droplet would result in the
20
decrease in spreading rate becoming quickly. Thus, the time To would become shorter.
21
In order to explain the differences in spreading rates of P507 organic droplets on
22
the surface of deionized water and on that of Er(III) aqueous solution, a theoretic 25
ACS Paragon Plus Environment
Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
1
calculation about the changes in spreading coefficient S of organic droplets on the
2
surface of different supporting liquids with the increase in P507 concentration, the
3
saponification degree of P507 extractant, and the pre-loaded erbium concentration in
4
the organic phase were performed, and the results were listed in Fig. 9. All of the
5
calculations about the spreading coefficient S were based on the experimental data
6
listed in Table S13 to S18 in Supporting Information.10
7
8 9
Figure 9. The changes in spreading coefficient S of P507 organic droplets with (a) the
10
concentration of P507, (b) the saponification degree of P507 extractant, and (c) the pre-loaded
11
Erbium concentration in the organic phase.
12 13 26
ACS Paragon Plus Environment
Page 26 of 36
Page 27 of 36 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
Langmuir
1
As can be seen in Fig. 9, the spreading coefficient S of P507 organic droplets on
2
the surface of Er(III) aqueous solution are larger than that on the surface of deionized
3
water. According to Svitova’s work, the transient precursor film radius obeys a simple
4
power scaling law in time elapsed t with the time exponent n (=3/4 theoretically
5
predicted).46 The increase in the spreading coefficient S would enhance the driving
6
force for the spreading. Therefore, the wettability of P507 organic droplets on the
7
surface of Er(III) aqueous solution was accelerated. In fact, the increase in the
8
wettability of P507 organic droplets on the surface of Er(III) aqueous solution might
9
be attributed to the occurrence of a chemical reaction at the interface between P507
10
oil membrane and Er(III) aqueous solution. The Marangoni convection was triggered
11
and therefore promote the mass transferring along the interface, which is favor of
12
overcoming the resistance from the viscous force when surface tension gradient
13
replaces the gravity as a dominant driving force for spreading. Thus, the spreading
14
rate of P507 oil membrane on the surface of Er(III) aqueous solution was enhanced.
15
Correspondingly, the time T0 for the spreading on the surface of Er(III) aqueous
16
solution was also shorten, compared to the spreading on the surface of deionized
17
water.
18 19
CONCLUSION
20
The present work demonstrated that the spreading of organic extractant P507 on
21
the surface of aqueous solutions containing rare-earth ions was accelerated due to the
22
occurrence of the chemical reactions at the gas-water interface. The difference in 27
ACS Paragon Plus Environment
Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
1
spreading rate of organic extractant P507 liquid droplets respectively on the surface of
2
deionized water and on that of Er(III) aqueous solutions with the increase in P507
3
concentration, the saponification degrees of P507 extractant and the pre-loading
4
amount of Er(III) in P507 extractant revealed that the chemical reaction at the
5
interface between the spreading P507 thin liquid membrane and Er(III) aqueous
6
solution would result in the Marangoni convection along the interface, which is favor
7
of overcoming the resistance from the viscous force when surface tension gradient
8
replaces the gravity as a dominant driving force for the spreading. The ratios of
9
viscosity to elasticity in organic droplets play a crucial role during the process of the
10
spreading, and have a significant impact on the formation of stable organic liquid film
11
on the surface of gas-water interface.
12
The present work provides an experimental foundation towards understanding
13
the effect of the interfacial chemical reaction on the spreading behavior of organic oil
14
droplet on the gas-water interface. It is beneficial for the development of our
15
suggested new technique of bubbling organic liquid membrane extraction, and to
16
achieve a controllable generation of stable gas bubble-supported organic liquid
17
membrane for performing solvent extraction at large aqueous-to-oil phase ratios.
18 19
Supporting Information
20
Details of the time-dependent changes in spreading area of the organic droplets with
21
different P507 concentrations, the saponification degrees of P507 extractant and the
22
pre-loading amount of Er(III) in organic solutions respectively on the surface of 28
ACS Paragon Plus Environment
Page 28 of 36
Page 29 of 36 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
Langmuir
1
deionized water and on the surface of Er(III) aqueous solutions; the schematic
2
diagram about how to obtain the time To for the transition point of the spreading rates;
3
the fitting equations of the spreading areas of the organic droplets with different P507
4
concentrations, the saponification degrees of P507 extractant and the pre-loading
5
amount of Er(III) in organic solution respectively on the surface of deionized water
6
and on the surface of Er(III) aqueous solutions; the elasticity modulus and viscous
7
modulus, and the viscosity of the organic phase with different P507 concentrations,
8
the saponification degrees of P507 extractant and the pre-loading amount of Er(III) in
9
organic solution; the surface tension and interfacial tension of the organic phase with
10
different P507 concentrations, the saponification degrees of P507 extractant and the
11
pre-loading amount of Er(III) in organic solution respectively on the surface of
12
deionized water and on the surface of Er(III) aqueous solutions.
13 14
NOTES
15
The authors declare no competing financial interest.
16 17
ACKNOWLEDGEMENTS
18
This work was financially supported by the National Natural Science Foundation of
19
China (Nos. 51574213, 21606248, 51074150), the Key Research and Development
20
Program of Shandong Province(2018GSF117028), and the Key Project of Chinese
21
National Programs for Fundamental Research and Development (973 Programs Nos.
22
2012CBA01203). 29
ACS Paragon Plus Environment
Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
Page 30 of 36
1 2
REFERENCES
3
[1] Sholl, D. S.; Lively, R. P. Seven Chemical Separations to Change the World,
4
Nature 2016, 532, 435-437.
5
[2] Huang, K.; Liu, J.; Wu, H. Z.; Liu, H. Z. A New Bubbling Extraction Tower:
6
Towards Liquid-Liquid Solvent Extraction at Large Aqueous-to-Oil Phase Ratios.
7
AlChE J. 2015, 61, 3889-3897.
8
[3] Liu, J.; Huang, K.; Wu, H. Z.; Liu, H. Z. A Feasible Strategy for Calculating the
9
Required Mass Transfer Height of a New Bubbling Organic Liquid Membrane
10
Extraction Tower Directly Based upon the Experimental Kinetic Data. Ind. Eng.
11
Chem. Res. 2016, 55, 4426-4434.
12
[4] Liu, J.; Huang, K.; Wu, X. H.; Liu, H. Z. Enrichment of Low Concentration Rare
13
Earths from Leach Solutions of Ion-Adsorption Ores by Bubbling Organic Liquid
14
Membrane Extraction Using N1923. ACS Sus. Chem. Eng. 2017, 5, 8070-8078.
15
[5] Liu, J.; Huang, K.; Wu, X. H.; Liu, W. Q.; Song, W. Y.; Liu, H. Z. Extraction of
16
Rare Earths Using Bubbling Organic Liquid Membrane with Un-saponified P507.
17
Hydrometallurgy 2018, 175, 340-347.
18
[6] Si, Y. F.; Yu, C. L.; Dong, Z. L.; Jiang, L. Wetting and Spreading: Fundamental
19
Theories to Cutting-Edge Applications. Curr. Opin. Colloid Interface Sci. 2018, 36,
20
10-19.
21
[7]
22
Surfactant-Enhanced Spreading ： Experimental Achievements and Possible
Kovalchuk,
N.
M.;
Trybala,
A.;
Arjmandi-Tash,
30
ACS Paragon Plus Environment
O.;
Starov,
V.
Page 31 of 36 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
Langmuir
1
Mechanisms. Adv. Colloid Interface Sci. 2016, 233, 155-160.
2
[8] Liang, G. T.; Mudawar, I. Review of Mass and Momentum Interactions During
3
Drop Impact on a Liquid Film. Int. J. Heat Mass Transfer 2016, 101, 577-599.
4
[9] Robinscn, J. V.; Woods, W. W. A General Method of Selecting Foam Inhibitors. J.
5
Soc. Chem. Ind. London 1948, 67, 361-383.
6
[10] Harkins, W. D.; Feldman, A. Films the Spreading of Liquids and the Spreading
7
Coefficient. J. Am. Chem. Soc. 1922, 44, 2665-2685.
8
[11] Hotrum, N. E.; Van Vliet, T.; Cohen Stuart, M. A.; Van Aken, G. A. Monitoring
9
Entering and Spreading of Emulsion Droplets at an Expanding Air/Water Interface: A
10
Novel Technique. J. Colloid Interface Sci. 2002, 247, 125-131.
11
[12] Foda, M.; Cox, R. G. The Spreading of Thin Liquid Films on a Water-Air
12
Interface. J. Fluid Mech. 1980, 101, 33-51.
13
[13] Chebbi, R. Inertia-Gravity Spreading of Oil on Water. Chem. Eng. Sci. 2000, 55,
14
4953-4960.
15
[14] Chebbi, R. Spreading of Oil on Water in the Surface-Tension Regime. Environ.
16
Fluid Mech. 2014, 14, 1443-1455.
17
[15] Camp, D. W.; Berg, J. C. The Spreading of Oil on Water in the Surface-Tension
18
Regime. J. Fluid Mech. 1987, 184, 445-462.
19
[16] Chengara, A.; Nikolov, A. D.; Wasan, D. T. Vertical Spreading of Aqueous
20
Trisiloxane Solution Driven by a Spontaneously Developing Surface Tension
21
Gradient. Ind. Eng. Chem. Res. 2008, 47, 3639-3644.
22
[17] Chengara, A.; Nikolov, A. D.; Wasan, D. T. Spreading of a Water Drop 31
ACS Paragon Plus Environment
Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
1
Triggered by the Surface Tension Gradient Created by the Localized Addition of a
2
Surfactant. Ind. Eng. Chem. Res. 2007, 46, 2987-2995.
3
[18] Koch, K.; Dew, B.; Corcoran, T. E.; Przybycien, T. M.; Tilton, R. D.; Garoff, S.
4
Surface Tension Gradient Driven Spreading on Aqueous Mucin Solutions: A Possible
5
Route to Enhanced Pulmonary Drug Delivery. Mol. Pharmaceut 2011, 8, 387-394.
6
[19] Carles, P.; Cazabat, A. M.; Kolb, E. The Spreading of Films by Surface-Tension
7
Gradients. Colloids Surfaces A 1993, 79, 65-70.
8
[20] Thess, A. Stokes Flow at Infinite Marangoni Number: Exact Solutions for the
9
Spreading and Collapse of a Surfactant. Phys. Scripta 1996, T67, 96-100.
10
[21] Roques-Carmes, T.; Babak, V.; Mathieu, V.; Gigante, A. Influence of Drop
11
Volume and Surfactant Concentration on the Marangoni Flow and Contact Line
12
Instabilities during the Spreading of Surfactant Solutions on Hydrophilic Surface. J.
13
Dispersion Sci. Technol. 2013, 34, 1053-1066.
14
[22] Hernández-Sánchez, J. F.; Eddi, A.; Snoeijer, J. H. Marangoni Spreading due to a
15
Localized Alcohol Supply on a Thin Water Film. Phys. Fluids 2015, 27, 032003, DOI:
16
10.1063/1.4915283.
17
[23] Tarasov, V. V.; Patanina, V. V.; Zhang, D. X. Influence of the Marangoni Effect
18
on the Spreading of Macroquantities of Organic Liquids on Water. Theor. Found.
19
Chem. Eng. 2008, 42, 832-836.
20
[24] Berg, S. Marangoni-Driven Spreading along Liquid-Liquid Interfaces. Phys.
21
Fluids 2009, 21, 032105, DOI: 10.1063/1.3086039.
22
[25] Tsuchitani, S.; Fukutake, T.; Mukai, D.; Miki, H.; Kikuchi, K. Unstable 32
ACS Paragon Plus Environment
Page 32 of 36
Page 33 of 36 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
Langmuir
1
Spreading of Ionic Liquids on an Aqueous Substrate. Langmuir 2017, 33,
2
11040-11046.
3
[26] Bauget, F.; Langevin, D.; Lenormand, R. Dynamic Surface Properties of
4
Asphaltenes and Resins at the Oil-Air Interface. J. Colloid Interface Sci. 2011, 239,
5
501-508.
6
[27] Yu, W.; Zhou, C. X. Dynamics of Droplet with Viscoelastic Interface. Soft
7
Matter 2011, 7, 6337-6346.
8
[28] Fanton, X.; Cazabat, A. M. Spreading and Instabilities Induced by a Solutal
9
Marangoni Effect. Langmuir 1998, 14, 2554-2561.
10
[29] Gambaryan-Roisman, T. Modulation of Marangoni Convection in Liquid Films.
11
Adv. Colloid Interface Sci. 2015, 222, 319-331.
12
[30] Kovalchuk, N. M.; Vollhardt, D. Marangoni Instability and Spontaneous
13
Non-linear Oscillations Produced at Liquid Interfaces by Surfactant Transfer. Adv.
14
Colloid Interface Sci. 2006, 120, 1-31.
15
[31] Wu, W. Y.; Li, D.; Zhao, Z. H.; Chen, J. L.; Zhang, F. Y.; Yin, S. H.; Qian, M. L.;
16
Bian, X. Formation Mechanism of Micro Emulsion on Aluminum and Lanthanum
17
Extraction in P507-HCl System. J. Rare Earths 2010, 28, 174-178.
18
[32] Werner, S. R. L.; Jones, J. R.; Paterson, A. H. J.; Archer, R. H.; Pearce, D. L.
19
Droplet Impact and Spreading: Droplet Formulation Effects. Chem. Eng. Sci. 2007, 62,
20
2336-2345.
21
[33] Soucková, M.; Klomfar, J.; Pátek, J. Temperature Dependence of the Surface
22
Tension and 0.1 MPa Density for 1-C-n-3-Methylimidazolium Tris (Pentafluoroethyl) 33
ACS Paragon Plus Environment
Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
1
Trifluorophosphate with n =2, 4, and 6. J. Chem. Thermodyn. 2012, 48, 267-275.
2
[34] Klomfar, J.; Soucková, M.; Pátek, J. Surface Tension Measurements with
3
Validated Accuracy for Four 1-Alkyl-3-Methylimidazolium Based Ionic Liquids. J.
4
Chem. Thermodyn. 2010, 42, 323-329.
5
[35] Wang, Y.; Ge, J. J.; Zheng, Y. F.; Jiang, P.; Zhang, G. C. A Study of
6
Relationship Between Oil-Water Interfacial Dilational Rheology and Oil Recovery of
7
Alkaline Flooding. Tenside Surfact. Det. 2015, 52, 294-300.
8
[36] Alteraifi, A.M.; Sherif, D.; Moet, A. Interfacial Effects in the Spreading Kinetics
9
of Liquid Droplets on Solid Substrates. J. Colloid Interf. Sci. 2003, 264, 221-227.
10
[37] Hotruma, N. E.; Stuart, M. A. C.; van Vliet, T.; van Aken, G. A. Spreading of
11
Partially Crystallized Oil Droplets on an Air/Water Interface. Colloids Surfaces A
12
2004, 240, 83-92.
13
[38] Wu, Z. C. A Comment on Fay’s Formulae about the Spread of Oil Slick on
14
Water
15
Surface. Applied Mechanics and Materials 2013, 420, 259-262.
16
[39] Wang, L. S.; Huang, X. W.; Yu, Y.; Long, Z. Q. Kinetics of Rare Earth
17
Pre-loading with 2-Ethylhexyl Phosphoric Acid Mono 2-Ethylhexyl Ester
18
[HEH(EHP)] using Rare Earth Carbonates. Sep. Purif. Technol. 2014, 122, 490-494.
19
[40] Chebbi, R. Spreading of Steadily-Discharged Oil on Water in the
20
Viscous-Gravity Stage. Chem. Eng. Sci. 2013, 98, 311-316.
21
[41] Matsubara, H.; Aratono, A.; Wilkinson, K. M.; Bain, C. D. Lattice Model for the
22
Wetting Transition of Alkanes on Aqueous Surfactant Solutions. Langmuir 2006, 22, 34
ACS Paragon Plus Environment
Page 34 of 36
Page 35 of 36 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
Langmuir
1
982-988.
2
[42] Liu, H.; Xu, X. M.; Guo, S. D. Rheological, Texture and Sensory Properties of
3
Low-Fat Mayonnaise with Different Fat Mimetics. LWT-Food Sci. Technol. 2007,
4
40, 946-954.
5
[43] Stenvot, C.; Langevin, D. Study of Viscoelasticity of Soluble Monolayers Using
6
Analysis of Propagation of Excited Capillary Waves. Langmuir 1988, 4, 1179-1183.
7
[44] Ravera, F.; Loglio, G.; Kovalchuk, V. I. Interfacial Dilational Rheology by
8
Oscillating Bubble/Drop Methods. Curr. Opin. Colloid Interface Sci. 2010, 15,
9
217-228.
10
[45] Hotrum, N. E.; Stuart, M. A. C.; van Vliet, T.; van Aken, G. A. Spreading of
11
Partially Crystallized Oil Droplets on an Air/Water Interface. Colloids Surf. A 2004,
12
240, 83-92.
13
[46] Svitova, T. F.; Hill, R. M.; Radke, C. J. Spreading of Aqueous
14
Dimethyldidodecylammonium Bromide Surfactant Droplets over Liquid Hydrocarbon
15
Substrates. Langmuir 1999, 15, 7392-7402.
16 17 18 19 20
35
ACS Paragon Plus Environment
Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
1 2
TOC graphic
3
4 5 6 7 8 9 10 11 12
36
ACS Paragon Plus Environment
Page 36 of 36
